PACIFIC RAPTOR GOLDEN GATE RAPTOR OBSERVATORY
ISSUE 41 FALL MIGRATION PUBLISHED AUGUST 2020 2019 Red-tailed Hawk. Photo: Veronica Pedraza Front Cover Artwork: Sharp-shinned Hawk (Accipiter striatus) migrating past Hawk Hill. 12x16 Gouache painting on paper by Bryce W. Robinson. Bryce is an ornithologist and illustrator who works to integrate visual media and research to better communicate topics in ornithology. You can see more of Bryce's work at www.ornithologi.com.
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FEATURE CONTENTS
1 Announcements 3 DIRECTOR'S NOTE Raptors in Light of Climate Change
HAWKWATCH 7 The Complex Art of "Seeing" Reptors 9 Measuring the Rate of Raptors
BANDING 15 Training the Next Generation of Raptor Biologists 19 Changes in Migrating Accipiters
BAND RECOVERIES & ENCOUNTERS 25 GGRO Recovery Data Supports Airport Safety 29 Recent Records 41 Turkey Vulture Update: The Story of 368 43 OUTREACH Five Years of Migratory Story 45 Pinnacles National Park: Unexpected Nest-Mates 47 INTERN INTERVIEW Dr. Linnea Hall 51 PEREGRINATIONS Winter Raptors at Lynch Canyon
PACIFIC RAPTOR 3 GGRO bander and docent Lynn Schofield releases a Cooper's Hawk at a weekend Hawk Talk program. Photo: Paula Eberle
4 FALL MIGRATION 2019 INTRODUCTION
INTRODUCTION
Dear Friend of the GGRO,
e write this in September 2020, when many uncertainties about the COVID-19 pandemic remain. For more than three decades, the Parks W Conservancy has invited people to the Golden Gate National Parks to support deep and meaningful ecological work through community science. And when the time is right, when we can assure physical distancing and other safety measures, we look forward to continuing to do exactly that once again.
Together, we will cultivate and restore native landscapes, we will monitor at-risk and endangered species, and we will keep a pulse on the bird of prey populations of California at the largest raptor migration site in the Pacific states.
Thank you for supporting our important work, as a volunteer, donor or an impassioned bird lover. As you read through this year’s Pacific Raptor, reporting on the 2019 season of the Golden Gate Raptor Observatory, we hope you take great pride in your role in preserving and protecting our wild landscapes. GGRO is one of the Golden Gate National Parks Conservancy’s flagship community science programs, and you are what makes it possible!
Thank you for your ongoing support for the Parks Conservancy’s mission and future, and for all that you do to preserve these precious national parklands. •
Allen Fish GGRO Director, Golden Gate National Parks Conservancy
Christine Lehnertz President & CEO, Golden Gate National Parks Conservancy
PACIFIC RAPTOR 5 ANNOUNCEMENTS
2019 PRESENTATIONS AND PUBLICATIONS
long with generating an enormous The two UC Davis articles were headed up amount of original information by doctoral candidate and GGRO bander, A on California raptor movements Ryan Bourbour. One was a collaborative and ecology, the GGRO relies on excellent paper with US Fish and Wildlife Service relationships with more than a dozen biologists examining mercury loads in academic labs, government agencies, and feathers at migration stations like GGRO NGO’s to leverage the greatest amount across the United States. The other was of science from our work. Many research a methodological review of a technique projects take years to develop, analyze, and pioneered in the Hull lab using DNA to produce results; more years are required determine the prey species of hawks by to publish. In 2019, our collaborations swabbing the bills and feet of the raptors. resulted in three journal publications, two from Dr. Joshua Hull’s lab at the University of California, Davis, and one from Dr. Chris Briggs’ lab at Hamilton College in New York.
Doctoral candidate and GGRO bander Ryan Bourbour. 2018 GGRO Intern Laura Kwasnoski. Photo: Nelia White Photo: Ryan Bourbour
1 FALL MIGRATION 2019 ANNOUNCEMENTS
Prey DNA samples collected from talons and beaks of raptors banded at GGRO. Photo: Ryan Bourbour
Bourbour, RP, BL Martinico, MM Crane, AC Hull, Kwasnoski, LA, KA Dudus, AM Fish, EV and JM Hull. 2019. Messy eaters: Swabbing Abernathy, and CW Briggs. 2019. Examining prey DNA from the exterior of inconspicuous sublethal effects of anticoagulant rodenticides predators when foraging cannot be observed. on haemosporidian parasitemia and body Ecology and Evolution. doi: 10.1002/ece3.4866 condition in migratory Red-tailed Hawks. Journal of Raptor Research 53 (4): 402-409. Bourbour, RP, BL Martinico, JT Ackerman, MP Herzog, AC Hull, AM Fish, and JM Many other GGRO research projects are Hull. 2019. Interspecies, temporal, and in the works—seeds and saplings moving geographic comparisons of feather mercury toward tree status in the coming years. concentrations in North American raptors Three manuscripts have been submitted for sampled at migration monitoring stations. publication in 2020. If there is a common Ecotoxicology. doi: 10.1007/s10646-019-0216-2 theme in the more than eighty scientific articles produced through the GGRO, it would Hamilton College undergrad and GGRO intern have to be collaboration—between academics Laura Kwasnoski led an analysis looking for and volunteers, between agency biologists health impacts of rat poisons on Red-tailed and grad students—a commitment to getting Hawks banded at GGRO. Laura included the the science done and out to the world. Great work and talents of two other former GGRO gratitude to all of our past and present interns, Kristina Dudus and Emily Abernathy, collaborators for investing your time and in her research. energy with GGRO. •
PACIFIC RAPTOR 2 DIRECTOR'S NOTE
RAPTOR S I N L I GH T O F CLIMATE CHANGE
Allen Fish
ast fall, I got word of juvenile birds, so they could a new scientific article track dates for the start and L on climate change and end of the first autumn molt. birds. Three biologists at the Some of these species molt University of Haifa and Tel- before autumn migration, Hai College in Israel—Yosef some after. What did Kian GGRO Director Allen Fish takes a selfie break on a Kiat, Yoni Vortman, and Nir foggy afternoon at Hawk Hill. Photo: Allen Fish and his team find? Sapir—had just published an article titled “Feather moult and bird appearance After plotting their molt data against a measure of are correlated with global warming over the last climate change called Global Mean Temperature 200 years.” What? A 200-year dataset? How is Anomalies (GMTA), they found three results over that possible? And even more amazing: climate the 200+ years of data: (1) the amount of molt change can impact the look of a bird, its very increased for 16 of the 19 songbird species; (2) for plumage? I found a PDF of the original article from ten species that showed different adult plumages Nature Communications and started reading. in males and females, female birds progressed toward adult plumage faster in four species since 1990; and (3) this pattern of increasing CLIMATE CHANGE CORRELATES molt extent over time appeared in all three WITH PLUMAGE CHANGES categories—year-round resident species, short- To obtain a two-century dataset, Kian and team distance, and long-distance migrating species. visited ten major natural history museums across Europe, scoring the extent of molt on 4012 bird To grab a mental picture of why this might be specimens from the years 1805 to 2016. They happening, think of a generic calendar year, January focused on nineteen species of songbirds, only through December, stretched out on a horizontal
ALLEN FISH, hired as GGRO Director in 1985, was the Golden Gate National Parks Conservancy’s first bird biologist. With a background in evolutionary ecology from UC Davis, Allen has an interest in bird population responses to urbanness, climate change, and other human impacts. He is equally fascinated by human responses to wild birds.
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axis, left to right. One of the general findings of climate change research in the last decade is that many birds nest earlier as spring temps start earlier (breeding season shifts left). Another finding is that autumn migration is delayed, as winter temps are delayed (migration season shifts right). These two patterns have the net effect of “opening up” the post-breeding juvenile molt “season” that resides between fledging and the onset of migration. Presumably, the bird does not show much overlap in breeding, molt, and migration because each is a very energetically expensive activity.
There is a lot more to think about in Kian’s paper and I encourage you to read the original article which, in my mind, deserves a place in history. Why? For one, how many bird studies have 200-year datasets? Also, this is great proof of the value of museum collections, perhaps the most important validation since Dan Anderson crossed the continent to measure 1400 Peregrine Falcon eggshells in This young Red-tailed Hawk resists a light February snow in the mountains of California. Photo: Pamela Rose Hawken the mid-sixties to document the impact of DDT. Hawk in North America. Redshoulders take a great So, what do we know about raptors and climate range of prey, largely what is found in a riparian change from the scientific literature? There forest, from snail to stickleback, shrew to squirrel, are many general patterns and models about and songbird to pheasant. So not only is the how birds in general might respond to climate Redshoulder positioned a bit higher up the trophic change, but do birds of prey present a different ladder than the Honey Buzzard, but as a generalist situation? Maybe a better way to ask this is: do predator it has greater nimbleness in its ability to predatory birds respond differently to climate switch prey types in the face of low prey numbers. change than bird species at other places on the trophic (food) landscape? Of course, they might. ARE RAPTOR MIGRATIONS SHIFTING? One of the primary effects of climate change has Another area of climate and raptor study focuses been the shifting of phenologies (dates) of events, on the phenology of migration. With many raptor as Kian et al. (2019) showed in their molt study. migration databases available around the world, Imagine for a minute the climate impact on a raptor climate ecologists are beginning to compile species that is highly dependent on insect prey, such regional counts to see if climate-related shifts as the European Honey Buzzard, eater of hornets show up. Jean-Francois Therrien of Hawk Mountain and wasps. Whatever impact the climate has on Sanctuary, PA, and colleagues (2017) used 25-year wasps will likely befall Honey Buzzards. Contrast this autumn raptor counts from sites stretched from with a generalist predator like the Red-shouldered Duluth eastward across the Great Lakes to the
PACIFIC RAPTOR 4 DIRECTOR'S NOTE
Olivia Wang presents "Changes in the Autumn Migration Timing of Two North American Raptor Species" at the UC Davis Undergraduate Research Conference in 2018. Olivia Wang later joined GGRO as an intern for the 2018 season. Photo: Olivia Wang
East Coast. They found that autumn migration had migrants, larger species, and diet specialists.” In delayed on average by one day per ten years, but other words, an Osprey on course for wintering this wasn’t all. The most pronounced delays were in the South American tropics has a 30-million- seen in short-term migrants, like Sharp-shinned year-old, hard-wired genetic program to migrate Hawks and Merlins, while long-distance, trans- quickly to reach those warm fishable coastlines. equatorial migrants like Peregrine Falcons and A Sharp-shinned Hawk, dependent on small Osprey showed no delay at all. Why should that be? bird prey, can adjust its migration based on winter prey supply, on competition for prey, or—presumably—climate-related cues, such …whatever anomalous hawk as temperature, wind-speed, and direction. behavior we can observe, they all carry the potential to GOLDEN GATE PHENOLOGICAL SHIFTS In 2018, Olivia Wang and Joshua Hull of UC Davis illuminate a clearer picture analyzed GGRO data for Sharp-shinned and Cooper’s Hawks, to sleuth out any phenological of what is happening more shifts for the Hawk Hill counts from 1992 through broadly in natural landscapes 2016. Here’s what they learned: no shifts for Cooper’s Hawks, however Sharp-shinned Hawks during this era of profound delayed their start of migration by 7.5 days over 25 years, and their half-way migration point by 5.5 days. climate impact. We so often think of Cooper’s and Sharpshins as sister species, one just slightly bigger Therrien et al. (2017) hypothesize that “raptor than the other, so why should their migration species with a greater potential for adjustment— phenologies be so different? Why should climate that is, short-distance migrants, small species, change affect Sharpshins more profoundly than and diet generalists—would exhibit a greater Cooper’s Hawks? A few reasons I can think of: phenological response than would long-distance
5 FALL MIGRATION 2019 DIRECTOR'S NOTE DIRECTOR'S NOTE
First, Cooper’s are a pretty common year-round Third, Sharpshins are small—one quarter to raptor species in the San Francisco Bay Area, one-half the mass of a Cooper’s Hawk. Given whereas Sharpshins arrive for fall migration, stay surface-to-volume ratios, this means that Sharp- for the winter (or migrate south), and mostly leave shinned Hawks must eat more and hunt more. in the breeding season. There are a few Sharpshin They must stay on top of their prey supplies nests in the SF Bay Area region, but they are rare more constantly and vigorously than a Cooper’s and mostly in thick conifer forests. Why should Hawk, on average. This requires that they stay local nesting have an impact on phenological shifts? physically close to their prey, even tracking There are so many local young Cooper’s Hawks in the migratory movements of songbirds. the Bay Area each summer and fall, I think they swamp the chance to measure a change in migratory THE COLOSSAL CLIMATE phenology in that species at the Golden Gate. The great biologist Theodosius Dobzhansky once wrote: “Nothing makes sense in biology except in the light of evolution.” I missed Dr. Dobzhansky at UC Davis by just four years, having arrived there in 1979, a fresh-scrubbed, dorky but passionate student of birds. Although Dobzhansky died in 1975, I wonder if today he might have revised his famous quote to add “…in the light of evolution and climate change.”
Long-term, consistently-collected data about the natural world have never been more important The Red-shouldered Hawk is a prey generalist, making it more capable than they are today. And although it is difficult to of tolerating climate and ecological change. Photo: George Eade. make sense of raptor population changes in light
Second, as mentioned above, Sharp-shinned of climate change or evolution, it is critical for us Hawks are small bird predators. Cooper’s Hawks to try to do so. Why? Because whatever patterns are more flexible in their diets, sometimes taking we can detect and dissect, whatever anomalous as many herptiles and mammals as birds. Some hawk behavior we can observe, they all carry the songbird species (warblers, tanagers, vireos, potential to illuminate a clearer picture of what sparrows) are highly migratory, requiring the is happening more broadly in natural landscapes Sharpshin to be more migratory as well. Cooper’s, during this era of profound climate impact. • of course, also eat migratory birds, but they have more options as far as shifting their hunts to more slow-moving, terrestrial prey as well.
Kiat, Y, et al. 2019. Feather moult and bird appearance are correlated with global warming over the last 200 years. Nature Communications 10: 2450. doi: 10.1038/s41467-019-10452-1.
Terraube, J, et al. 2015. Coping with fast climate change in northern ecosystems: mechanisms underlying the population-level response of a specialist avian predator. Ecography 38: 690-699. doi: 10.1111/ecog.01024.
Therrien, JF, et al. 2017. Long-term phenological shifts in migration and breeding–area residency in eastern North American raptors. Auk (Ornithological Advances) 134: 871-881. doi: 10.1642/AUK-17-5.1.
PACIFIC RAPTOR 6 HAWKWATCH 2019
TH E CO M P LE X ART O F “SEEING” HAWKS
Catherine Elliot
he Broad-winged Broad-winged hawk) or Hawk suddenly dark streaking (a sign T appeared above that the Broad-winged me—closer than I had ever hawk is a first-year bird). seen one, maybe just thirty feet above. I was startled That day reminded me and delighted, because I again that “seeing” had only seen “Broadies” hawks is a complex as far off specks in the sky. art. In that moment, I This one had soared up saw only a couple key Catherine Elliot and her husband Tom Luster both volunteer on the features of the hawk above me for a moment, Wednesday 1 Hawkwatch Team. Photo: Gretchen Zantzinger and then it was gone. and no more. How could I miss the color of the I was still reeling with amazement when Christine hawk’s body when I was looking straight up at it? Cariño, our excellent Wednesday hawkwatch dayleader, asked me whether the Broad-winged Sometimes I think watching hawks is like watching was an adult or juvenile. I remembered seeing the a fast play in a Warriors basketball game—I don’t hawk’s classic silhouette—like a Red-tailed Hawk see all the details of a complex play the first time but with shorter, broader wings—and its light white around, especially if I think about something else underwings. I couldn’t remember anything else. for even a moment. But with a basketball game Christine reminded me to look next time for rufous on TV, I can rewind the play, watch again while barring on the chest (the plumage of an adult listening to the commentators, and learn. We can’t rewind a bird’s flight, but I work to improve my
CATHERINE ELLIOT has been a hawkwatcher for over four years. In her professional life, Catherine protects redwood forests to conserve their important bird and wildlife habitat and to provide lovely places for people to enjoy.
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skills by looking at each new bird and learning from what Christine and my other hawkwatch team members point out. They’re gracious and fun, and we enjoy helping each other learn and collect the most accurate data we can.
During each season, our team witnesses up to nineteen raptor species migrating through the Golden Gate. I’m glad to see each bird. I’m proud to volunteer at GGRO and contribute to its long legacy of data collection for scientific study, but what keeps me coming back is to share the joy and sense of awe with others who delight in these hawks’ migrations, and yes, to “see” the hawks better. 2019 Interns Emma Regnier and Maggie Brown scan for raptors in • the east quadrant. Photo: Allen Fish
A juvenile Broad-winged Hawk, age indicated by the dark streaking on its chest, photographed from Hawk Hill during the 2019 season. Photo: Willie Hall
PACIFIC RAPTOR 8 HAWKWATCH 2019
MEASURING THE RATE OF RAPTORS
Step Wilson
awk counting at be sure if the newly seen the Golden Gate female American Kestrel H Raptor Observatory is the same one that was has its own idiosyncrasies, spotted ten minutes ago in protocols, and set of the same area or whether assumptions, as do other it’s a new one that should count sites across the be added to our count. country and the world. Rough-legged Hawk photographed at Lynch Canyon December 2019. Photo: John Davis In conjunction with The rugged topography this protocol is a key of the Marin Headlands creates challenges for assumption that raptors will pass and re-pass counting—the many hills and valleys make it through our count site at the same rate from year difficult to maintain continuous sight of a raptor to year. It is one of the reasons we refer to our before it crosses the Golden Gate or meanders its total count as sightings and why we reference the way through this prey-heavy area.One of our main raptors per hour data more than the total count. protocols is to use the quadrant system where a
team of two or more counters face each of the Are these factors a cause for alarm? Do they negate cardinal directions to identify, record, and pass our data? Are we doing good science? I don’t counted birds. This system of “passing” recorded think so, no, and I believe we are. Let me explain. birds from one quadrant to the next lowers the possibility of duplication. Additionally, if a raptor has I don’t believe it is a cause for alarm because many not been tracked in that quadrant or passed from hawk count stations have protocols and assumptions another and appears after ten minutes of not being that they use as well. For example, many stations seen, it goes on the count as a new sighting. This use an imaginary line that raptors must pass in order protocol relies on the assumption that one cannot to be added to the count. Do these lines always determine true migrants? What’s to stop the raptors
STEP WILSON came to GGRO as a bander in 1995 and caught the raptor bug, committing the next twenty years to raptor studies in Mexico, Israel, and across the American West. Step returned to GGRO in 2016 to be GGRO’s first Hawkwatch/Outreach Manager.
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from turning around out of sight and passing the during high wind days, smoke days, and power magic line again? Some stations use a maximum shutdowns demanded reevaluation of our safety (simultaneously) daily sighted method for counting preparedness and park policies around volunteer Turkey Vultures or Red-tailed Hawks. Might some work during these events. The landscape of our of these raptors roost locally and meander again in work environment is changing as is the climate. front of the counters the next day or even later?
Most sites do not count “local” or resident birds. Some behaviors and movements lend themselves to easily determine local status, but what happens when the locals are not acting local? I admit that all migration stations encounter inherent difficulties in counting hawks at their respective locations. All counts have implemented approaches to deal with their specific situations, and consistent dedication and adherence to these protocols is what makes Hawkwatchers gather in the north quadrant for a raptor ID study. them reliable from year to year. I believe our During these ID studies, banders release a bird that has been ID'd, count site meets the requirements stated in the aged, and sexed, into the north quadrant for hawkwacthers to test their identification skills. Photo: Nelia White first criteria of the Hawk Migration Association of North America (HMANA 2006), which states: “A GGRO misses count days due to dense fog or monitoring program should provide three types of heavy rain. More recently count days have been information: (1) An estimate/sample of population missed because of excessive heat, wildfires, poor size, (2) An estimate of demographic parameters air quality, and power outages. While noise and (e.g. information on population structure provided activity during last year’s new trail construction by data on species’ sex and age classes), and (3) likely influenced GGRO’s count, this season‘s count A measure of the environmental variables believed was conducted while helicopters flew within the to affect the first two estimates. It is expected that vicinity of the count site. Take-offs and landings this protocol and its revised contents continue to were all done within a quarter mile of Hawk Hill, be clear, simple, and practical for citizen scientists potentially diverting raptor flights from the area. and field biologists collecting data in the field, Although the work being performed around the but also useful and informative for the needs count and banding sites didn’t stop our efforts, it of managers, conservationists, and scientists in surely impacted both programs in some manner as later data analysis. This protocol can be easily the helicopter flights continued into September. customized for the particularities of a specific site.” Most of the distortion in this year’s count data The hawk migration conducted in the autumn of came from low numbers counted and banded for 2019 was not typical, consistent, or certain. It was Sharp-shinned Hawks. Sharpshins are the third full of changing protocols. Not the protocols we highest counted and second most banded raptor by use to count migrating raptors, but the protocols our volunteers. Having their numbers drop for the we need to allow volunteers to go out and count season impacts counters and banders alike, but is it the raptors. Considerations for volunteer safety concern for the future of Sharpshins themselves?
PACIFIC RAPTOR 10 HAWKWATCH 2019
to encounter. Maybe it’s because they are traveling great distances before they arrive here or because they vary significantly in their field marks within the same species. Or maybe it’s due to their low numbers and late arrival that we anticipate and await them. Or perhaps it is the pizza prize, started so long ago at GGRO, for the first Rough-legged Hawk sighting that invigorates volunteer excitement.
Harlan's Hawk seen from Hawk Hill during the 2019 season. Photo: Step Wilson
It appears that Sharp-shinned Hawk migration through the Marin Headlands could be on a four or five-year cycle. Looking at the count data from 1991 onwards, there is a significant dip every four or five years which continues usually into the next year before the numbers rise again (Page 20, Figure A juvenile Sharp-shinned Hawk flies past Hawk Hill after a 2). The first one is in 1996 and 1997 dropping to successful hunt, indicated by this individual's full crop, a part of the 5.48 and 3.86 raptors per hour (rph) respectively, bird's digestive track used to store food. Photo: George Eade then again in 2000 at 4.51, 2004 at 6.15, and 2009 Even though Ferruginous, Red-tailed, and at 6.7 rph. There was another dip in 2013 but that Swainson’s Hawk also have different color morphs, count was also affected by reduced October count something about Rough-legged and Harlan’s days due to the government shutdown that year. Hawks piques our interest. In any case, our interest Those lost count days coincide with the peak of is piqued and usually satisfied once a season. But Sharp-shinned Hawk migration. The five years this year, both species were seen at least twice in after that lacked a low point even though the one day. The first was two Rough-legged Hawks count has been generally lower than in seasons sighted on October 14—seen in a span of mere past. Will we have a rebound next year? Will we minutes adding to the excitement. Next was a have high counts of Sharpies as in years past? Is day of double Harlan’s sightings on November 3. there really a cycle with which this little accipiter Harlan’s Hawks are usually distinguishable with a is in rhythm? Next season and future year counts close enough view and these two were close. One will shed more light on some of these questions. was identified as an adult and the other a juvenile, which are harder to identify to subspecies. Some high points and phenomenal fun for the hawkwatchers and banders are Rough-legged and Amid all these challenges and experiences, the Harlan’s Hawks, the latter a subspecies of Red-tailed GGRO Hawkwatch continues and every year we Hawk. Both northern visitors are always a delight are thrilled by the magic the fall season brings. •
HMANA. 2006. Standard data collection protocol for raptor migration monitoring. http://rpi-project.org/docs/HMANA_Data_Collection_ Protocol_20060611.pdf
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RAPTOR SIGHTINGS - MARIN HEADLANDS
Autumn 2019* 10-Yr Average ('07-'18)** (443 hours) (478 hours)
Sightings Raptors/hr Sightings Raptors/hr
Turkey Vulture 7340 16.57 7577 15.81
Osprey 58 0.13 74 0.15
White-tailed Kite 31 0.07 68 0.14
Bald Eagle 19 0.04 9 0.02
Northern Harrier 807 1.82 562 1.18
Sharp-shinned Hawk 2021 4.56 3666 7.67
Cooper’s Hawk 2629 5.93 2330 4.87
Northern Goshawk 0 0 1 <0.01
Red-shouldered Hawk 280 0.63 445 0.93
Broad-winged Hawk 110 0.25 286 0.60
Swainson’s Hawk 4 0.01 8 0.02
Red-tailed Hawk 8248 18.62 8477 17.73
Ferruginous Hawk 17 0.04 28 0.06
Rough-legged Hawk 8 0.02 5 0.01
Golden Eagle 13 0.03 18 0.04
American Kestrel 286 0.65 349 0.73
Merlin 156 0.35 187 0.39
Peregrine Falcon 196 0.44 233 0.49
Prairie Falcon 0 0 5 0.01
Unidentified 784 1.77 1059 2.22
Total 23,007 51.93 25,387 53.11
*2019 hawk count lost six days due to power shutdowns and park closures **2010 and 2013 data not included due to partial season
PACIFIC RAPTOR 12 13 FALL MIGRATION 2019 Sketches and Stories from the 2019 Golden Gate Migration," 15.5" x 10.5" digital collage of pen and ink drawings with digital color by 2019 GGRO Intern Emma Regnier. Emma is a naturalist and mixed-media artist who is eager to share her passion for conservation and the natural sciences through her artwork. You can see more of Emma's work at https://falcofous.wordpress.com/
PACIFIC RAPTOR 14 BANDING 2019 BANDING 2019
TRAINING THE NEXT GENERATION OF RAPTOR BIOLOGISTS
Ben Dudek
n a hot afternoon would fly into them? in late August, And once caught, how O I drove my do you safely hold grandmother’s Volvo and process raptors? sedan packed with all my I had previously only possessions up a washed- held one raptor, a out dirt road southeast of juvenile Merlin that Albuquerque, New Mexico was caught in a mist and wondered what the net while banding Banding Manager Teresa Ely and volunteer bander Ben Dudek prepare next two months had in to release a juvenile Sharp-shinned Hawk. Photo: Ben Dudek songbirds in Maine, store. After traveling the and I’m embarrassed country for two years working as a seasonal field to say I held the Merlin the same way I was trained biologist, I had signed on to work with HawkWatch to safely secure small birds, in the passerine International’s fall migration project in the Manzano banding grip. It was not the best way to secure a Mountains. I had experience banding a variety of feisty Merlin, as evidenced by my bloody cuticles. different birds, including seabirds, waterfowl, and And finally, and perhaps most desperately, would passerines from my previous jobs, but this would be I be able to tell the difference between a Sharp- my introduction to trapping and banding raptors. shinned Hawk and a Cooper’s Hawk in hand? The notoriously tricky identification of the two I had a lot of questions leading up to the start of accipiters was something I struggled with in the season, as any first-year raptor bander might. the field and I was worried I would embarrass First and foremost: how do you catch raptors? myself in front of the experienced lead bander. Would we set up double-high mist nets, as some passerine banding stations do, and hope raptors
BENJAMIN DUDEK joined GGRO as a bander in 2017 after spending the previous six fall migration seasons banding hawks as a seasonal biologist for HawkWatch International and as a volunteer with Intermountain Bird Observatory. Ben currently works as a wildlife biologist in the Bay Area.
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2019 Intern Paula Eberle releases a juvenile Red-tailed Hawk. Photo: Teresa Ely
As my luck would have it, the lead bander that close greatly improved my identification in the field. season in the Manzanos was former Golden Gate Raptor Observatory (GGRO) intern and Over the next two months, I was trained how to set future Banding Manager Teresa Ely. In addition up the trapping site, how to operate the lines and to her deft skills as a raptor biologist and her traps, and how to safely capture, extract, handle amiable personality, Teresa brought GGRO’s and measure and weigh raptors. During that season, rigorous approach to training with her. Teresa and I trapped together six days a week. Teresa spent many long days instructing me how to I quickly learned that hawks are attracted into a lure for different raptors, when it was safe to trigger trapping area and then caught with a series of a bow net, which handholds were necessary to take nets, including mist nets, dho-gazas, and bow nets. accurate morphological measurements, and how to Raptors are easily secured by firmly grasping the age and sex each species until she felt confident that legs, and large coffee cans create a dark, quiet, I was capable of running a trapping blind by myself. and safe space for raptors to be held while being measured. And the squared-off head of Cooper’s It was not until I joined GGRO in 2017 that I realized Hawks could be easily distinguished from the I had been put through the GGRO Apprentice round-headed and bug-eyed Sharp-shinned Hawks Program that first season in New Mexico. When in hand. The opportunity to observe these birds up Teresa asked me how I knew a particular bird was “settled” before triggering a bow net, when she
PACIFIC RAPTOR 16 BANDING 2019
raptors in the office and during local field trips, and apprentice banders start their time at GGRO by attending raptor ID classes and banding skills workshops. In their first couple days in the field, new interns and apprentices are shown everything that goes into a day at GGRO from setting up the trapping blind, luring for and capturing raptors, safely handling and processing different species, and collecting invaluable data from each bird. Protocols have been developed for almost every situation throughout the day and it can be overwhelming to take everything in as a new bander.
Even after three seasons at GGRO and six years of banding raptors before that, I find I do not always have all the answers out in the field. Questions from new banders force me to reevaluate my approach to each situation and always teach me something new. When faced with a daunting question or task, volunteers often respond with, “I’m sure there are instructions written for this,” 2019 Intern Emma Regnier processes a Red-shouldered Hawk. Photo: Veronica Pedraza and of course, there usually are. Over 35 years, GGRO has created and innovated many techniques checked my measurements on each species until she used for trapping migratory raptors, but the felt I was a proficient processor, or when she asked commitment to training new interns and volunteers me to diagnose and fix problems with each trap, she and fostering a sense of responsibility among 100+ was really evaluating my abilities as a siteleader. banding volunteers is perhaps the organization’s most impressive accomplishment. The banding Despite having been taught this way, I continue program has been honed over three decades and, to be impressed with GGRO volunteers' level of while there is always more to learn and improve effort and commitment to training interns and new upon, through the help of its volunteers, GGRO apprentices. Every year, GGRO accepts five or six has created a supportive learning environment to interns without much raptor handling experience. train the next generation of raptor enthusiasts. And every two years, around 25 apprentices, who sometimes have no experience with birds at all, join Banding raptors kick-started my passion for raptor the banding program. And yet, at the end of each ecology. That first year in New Mexico was slow season, several interns have become siteleaders numbers-wise by historical standards, but life- and apprentices are able to look back on a season changing for me as a young biologist. The season in which their skills and confidence working brought waves of accipiters, buteos, falcons, and with wild raptors have grown tremendously. eagles. An adult Northern Goshawk at the end of that season capped off an incredible fall and I was When I started at GGRO, I was impressed by the hooked. For the next three falls, I returned to New amount of training that happened before the season Mexico to trap and band raptors. I followed that even began. Interns spend their first month studying passion for raptors to graduate school at Boise State
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University, and eventually to a wildlife biology job in importantly, it provides an opportunity for me to the Bay Area. For the Bay Area community, GGRO work with and help train the next generation of offers a unique experience and the challenges of biologists and community scientists. Many first- time commitments to off-season tasks and trainings year apprentices will learn the skills they need to is buoyed by the opportunity to work closely become fully-fledged raptor banders in a few short with these amazing birds of prey, to observe the years and will continue to contribute to GGRO’s seasonal and annual variability of fall migration, community science program in myriad ways. Many and to continue to learn something new every day. interns will complete their internship at GGRO and head out across the country to continue The opportunity to volunteer with GGRO as a their passion for raptors by working on seasonal community scientist is important to me in so many field projects or at other raptor migration sites. ways. First, it is important to continue our long- term monitoring program by collecting data that As I watch GGRO interns develop a passion helps inform our knowledge of North American for working with raptors and continue into the raptor populations. By assessing population trends, world of field biology, I am reminded of my own we gain invaluable information on each species journey and how important that first season that migrates along the Pacific Flyway each year. was in developing my skills as a bander and raptor biologist. The commitment to training Second, as a wildlife biologist, GGRO gives me the and fostering a supportive learning environment opportunity to continue to learn and build skills are essential for our newest banders because out in the field with a group of other volunteers they will soon become the next generation of from diverse backgrounds. But perhaps most teachers for young aspiring biologists. •
Bander Allison Gee releases a juvenile Red-tailed Hawk against the backdrop of the Golden Gate and San Francisco Bay. Photo: Calvin Hom
PACIFIC RAPTOR 18 BANDING 2019
CHANGES IN MIGRATING ACCIPITERS
Teresa Ely
he most common question I heard in Sharp-shinned Hawks Banded at GGRO 2019 was, “Where are all the Sharpies?” T The low Sharp-shinned Hawk numbers coupled with GGRO program cancellations left people feeling a little disappointed by the end of the autumn migration season. We only YEARLY TOTAL YEARLY banded about 40% of the average number of Sharp-shinned Hawks: 181 compared to the previous 10-year average of 445 per year. YEAR Figure 1. Sharp-shinned Hawk banding totals at GGRO 1991-2019.
As many volunteers remember, 2013 was the season when the government shut down in early October during the peak two-week period for Sharpies, and that year, we banded just 173 Sharpshins. So, while 2013 was a low year, we know there were Sharpies migrating that could have been banded, which would 2019 Intern Emma Regnier releases a juvenile Cooper's Hawk. make 2019 the lowest Sharpie year to date at GGRO. Photo: Teresa Ely
There were of course early years at GGRO where A DEEP DIVE INTO SHARP-SHINNED the Sharpie numbers were lower, when the program HAWK COUNTS was experimenting with blind locations, so I Though we ended the 2019 season with a lower- examined our data starting from 1991, when the Hill than average number of newly banded raptors, 88 blind came into the scene (Figure 1). 2019 is the we still banded over 1000 raptors! We continue to second-lowest year on record for Sharp-shinned collect data points for an incredible and impressive Hawks banded in a season at GGRO. In fact, in dataset that spans 35 years. Researchers dream of 1991, with the brand new Hill 88 blind, volunteers datasets this big. My colleagues during grad school banded 186 Sharpies, five birds more than in 2019. were always jealous that I had over 18,000 kestrel
TERESA ELY was a GGRO Intern in 2008, then continued to work at raptor migration stations throughout the west and Mexico. She completed her master’s degree in Ecology, Evolution, and Behavior at the University of Nebraska, Lincoln before returning to GGRO as Banding Manager in 2016.
19 FALL MIGRATION 2019 BANDING 2019 BANDING 2019
Sharp-shinned Hawks Counted at GGRO data points, with about 1400 from GGRO, and the rest from other migration sites throughout the US. Like so many others, I wished we had a more successful 2019 season, but I also see the value in
another year of data, so I decided to dust-off my RpH RStudio skills and look more closely at our data.
We know that the metrics for banding and counting raptors are different, and that both datasets are YEAR Figure 2. Sharp-shinned Hawk Raptors per Hour (RpH) at GGRO important for different reasons. There are many 1991-2019. 2013 data not included due to incomplete season. factors for banding that can cause us to trap fewer and different birds than are counted. I et al. 2020). I have been thinking about the changes decided to look at the GGRO hawk count data to in body size of raptors for a few years now. Since see if there were any trends for Sharpies. There this was the subject of my master’s research (Ely are some high years and low years, however et al. 2018), I started investigating the GGRO when analyzing all the data points, the counts morphometric data to see if we captured any have remained steady over time (Figure 2). changes in accipiter body size over the years.
Even though our 2019 Sharpshin count numbers were In GGRO’s 35 years we have banded over 13,000 below average, I feel confident that this year was just Sharp-shinned Hawks and 16,000 Cooper’s Hawks. If a “low” year. We had weather patterns in the Pacific you multiply those by the number of measurements Northwest (e.g., late rainfall and cold springtime taken on each bird (8), that is more than 230,000 data temperatures) that might have had a negative effect points. I kept my statistics simple. We can let another on raptor nestling and fledgling survival in spring- grad student take it to the next level with principal summer 2019. It would be interesting to compare our component analyses, generalized additive models, or numbers from this season to other Intermountain Bayesian models. I used a linear regression to determine Western raptor migration sites that count more whether there was any change in culmen (bill length), adult hawks, to see if there was a comparative lull. hallux (the big talon on the back of the foot), tail, wing It is easy to get depressed about the 2019 Sharpie chord, and weight. I accounted for size differences numbers, but a friend once told me, “We only in sexes, ages, and seasonal changes, and I removed see ‘normal’ on a graph. Mother Nature usually birds with full crops (undigested prey) when analyzing plots those dots above or below the mean.” weight. I did not analyze trends in adult measurements because our sample size for adults is small. SEEKING CLUES IN ACCIPITER Sure enough, when we look at the data, accipiter MEASUREMENTS body size is changing over time (Table 1)! For If there is not an informative trend in the GGRO juvenile Sharp-shinned Hawk males and females, I count data for Sharpies, what else can the data saw a decrease in culmen and hallux. Wing chord tell us? There have been recent papers published decreased in juvenile females but remained steady about the body size of birds changing in response in males. Two interesting notes: (1) The tail lengths to climate change (Van Buskirk et al. 2010, Weeks of Sharpshins increased over time, although weight
PACIFIC RAPTOR 20 BANDING 2019
did not change over time. (2) For Cooper’s Hawks, measurements in hopes these data would be used in the hallux and the wing chord decreased, whereas the future to analyze long-term trends. tail length increased. Culmen only decreased significantly in males. Cooper’s Hawk weight did not WHY LOOK AT BODY CHANGE? change in either sex. There has been a lot of interest recently in the What does all this mean? The change in accipiter body body-size change of birds. More and more papers size was not uniform for all measurements, sexes, and are being published that examine changes in species, so background causes will not be easy to body size using long-term banding datasets or figure out. More in-depth analysis and research will series of museum specimens. There is a pattern be needed. But this is the reason we collect long-term that species of larger sizes are often found in morphometric data on each species that we band. colder environments and species of smaller sizes The first GGRO raptor banders decided to take these are found in warmer climates. Ecologists call this
CHANGE SEX METRIC % CHANGE SLOPE P-VALUE SHARP-SHINNED HAWK JUVENILE F -0.15 -1.24 -0.01 <0.01 Culmen (mm) M -0.18 -1.88 -0.01 <0.01 F 0.48 0.30 0.02 0.02 Tail (mm) M 0.51 0.38 0.02 0.04 F -0.14 -0.97 -0.01 <0.01 Hallux (mm) M -0.22 -1.92 -0.01 <0.01 F -0.85 -0.43 -0.03 <0.01 Wing Chord (mm) M -0.26 -0.16 -0.01 0.28 F 0.09 -0.05 <0.01 0.85 Weight (g) M -0.01 -0.01 <0.01 0.98 COOPER'S HAWK JUVENILE F -0.06 -0.34 <0.01 0.05 Culmen (mm) M -0.11 -0.74 <0.01 <0.01 F 0.58 0.27 0.02 <0.01 Tail (mm) M 1.33 0.70 0.05 <0.01 F -0.19 -0.83 -0.01 <0.01 Hallux (mm) M -0.16 -0.83 -0.01 <0.01 F -1.20 -0.49 -0.04 <0.01 Wing Chord (mm) M -1.43 -0.66 -0.05 <0.01 F 0.91 0.22 0.03 0.40 Weight (g) M 1.51 0.55 0.05 0.11
Table 1: Morphometric changes in female and male juvenile Sharp-shinned and Cooper’s Hawks from 1991 to 2019 in the Marin Headlands, CA. The p-values that are bold are < 0.05, which means there is a significant change.
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Bergmann’s Rule. It would make sense to associate a decrease in body size to warming trends in climate. However, other factors like food availability and shifts in diet can affect body-size change as well.
For example, Cattau et al. 2017 found evidence of rapid body size change in Snail Kites at the same time that their diet shifted from a native snail to the larger and invasive Island Apple Snail. In less Illustration of culmen length measurement from GGRO Bander's Manual. than a decade, kite bill-size increased, which makes the kites more efficient at extracting meat from the bigger snail shell. Another study, this one on Goshawks in Denmark, suggested that a diet shift to smaller prey—due to a decline in grouse—selected for a decrease in wing length. In addition, juvenile Goshawks’ bill length decreased, and juvenile females had shorter tarsi (legs) (Yom-Tov et al. 2006).
More thorough analysis is needed, but there does Illustration of hallux claw length measurement from GGRO Bander's Manual. appear to be a small change in body size in the accipiters migrating through the Marin Headlands over 30 years. Since weight is not changing, and measurements like tail length are increasing over time, we cannot say for certain that climate change is causing the body size changes we have measured. However, if passerines are getting smaller over time, decreasing prey size could influence the changes we are seeing in accipiter’s beak and claw lengths. The Illustration of wing chord versus flat wing measurement from GGRO Bander's Manual. next step would be to look at what the Sharp-shinned and Cooper’s hawks are eating, and to investigate if those prey species are getting smaller over time. •
Cattau, CE, RJ Flethcer, Jr, RT Kimball, CW Miller, and WM Kitchens. 2017. Rapid morphological change of a top predator with the invasion of a novel prey. Nature—Ecology and Evolution 2: 108-115. doi: 10.1038/s41559-017-0378-1
Ely, TE, CW Briggs, SE Hawks, GS Kaltenecker, DL Evans, FJ Nicoletti, J-F Therrien, O Allen, and JP DeLong. 2018. Morphological changes in American Kestrels (Falco sparverius) at continental migration sites. Global Ecology and Conservation 15. doi: 10.1016/j.gecco.2018.e00400
Van Buskirk, J, RS Mulvihill, and RC Leberman. 2010. Declining body sizes in North American birds associated with climate change. Oikos 119: 1047-1055. doi: 10.1111/j.1600-0706.2009.18349.x
Weeks, BC, DE Willard, AA Ellis, ML Witynski, M Hennen, and BM Winger. 2020. Shared morphological consequences of global warming in North American migratory birds. Ecology Letters 23.2: 316-325. doi: 10.1111/ele.13434
Yom-Tov, Y, and S Yom-Tov. 2006. Decrease in body size of Danish goshawks during the twentieth century. Journal of Ornithology 147: 644-647. doi: 10.1007/s10336-006-0090-4
PACIFIC RAPTOR 22 BANDING 2019
RAPTORS BANDED - MARIN HEADLANDS
Autumn 2019* Annual Average Totals (8/12/2019 - 1/2/2020) 1993-2018** 1983-2019
Northern Harrier 10 10.31 333
Sharp-shinned Hawk 181 470.12 13,254
Cooper’s Hawk 596 556.62 16,786
Northern Goshawk 0 0.23 7
Red-shouldered Hawk 15 16.15 480
Broad-winged Hawk o 1.58 46
Swainson’s Hawk 0 0.38 11
Red-tailed Hawk 227 306.92 10,551
Ferruginous Hawk 0 0.04 3
Rough-legged Hawk 0 0.15 6
Golden Eagle 0 0.04 2
American Kestrel 10 52.19 1492
Merlin 23 31.00 840
Peregrine Falcon 7 4.27 124
Prairie Falcon 0 1.77 50
Eurasian Kestrel 0 0.04 1
Total 1069 1452 43,996
*Data compiled by Teresa Ely; 2019 data are through January 2, 2020; 2019 banding lost six days due to power shutdowns and park closures **1993-2018 are used for this comparison due to similarity of methods and effort between those years and 2019
23 FALL MIGRATION 2019 Male American Kestrel. Kestrels are the smallest species banded at GGRO each autumn. Photo: Veronica Pedraza
PACIFIC RAPTOR 24 BAND RECOVERIES & ENCOUNTERS 2019
G GR O R ECOVE RY D ATA SUPPORTS AIRPORT SAFETY
Nancy Brink
n October 19, 2011, former GGRO research The young Redtail (now GGRO recovery #1129) was director Buzz Hull banded a juvenile recovered at San Francisco International Airport O male Red-tailed Hawk and sent him on on December 19, 2011, exactly two months after his way. We never know where a banded hawk’s its banding. Sadly, the hawk struck a plane’s right journey might lead us. We band hawks in hopes jet engine as it sped down the runway to take off. that someone will once again encounter them, The plane returned to the gate and fortunately, and that knowledge gained will be of practical or no one was injured. But it was a costly collision, scientific value in conserving raptor populations. destroying 22 of the engine’s 28 fan blades.
A few months after banding, GGRO received a Airport officials reported the strike to the Federal report on this young Redtail from the Bird Banding Aviation Administration (FAA), which entered it Lab (BBL), a United States Geological Survey in a National Wildlife Strike Database. A feather (USGS) program established in 1920 to support and DNA material were sent to the Smithsonian distribution of bands and management of banding Feather Identification Lab to confirm species. and encounter data for all bird species in North The band number was reported to BBL. America. GGRO reports its data for hawks banded When GGRO receives a BBL encounter report, each fall to BBL, which has accumulated more than volunteers swing into action to confirm data and 64 million records of banded birds. This includes expand the hawk’s story. Marion Weeks, who has nearly 2.5 million diurnal raptors and owls, 239,791 led GGRO’s band recovery efforts for more than 25 of which are Red-tailed Hawks. When someone years, notes that GGRO regularly receives reports encounters a banded raptor, they will hopefully of hawks, primarily Red-tailed Hawks, who have report it to BBL. The BBL database now contains been struck by aircraft or removed from airports. more than 4 million band encounter reports, including 89,424 encounters of diurnal raptors Airports are enticing locations for Redtails, and owls, 14,002 of which are Red-tailed Hawks. which seem to adapt readily to human
NANCY BRINK is a filmmaker and writer, who assists with band recovery follow up, and has enjoyed fall migrations as a GGRO bander for nearly twenty years.
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All of the large airports of the Pacific States provide occasional seasonal habitat for birds of prey. A Red-tailed Hawk is seen here perch-hunting at Portland International Airport. Photo: Carole Hallett
presence. Runways straddle open fields. Strips wildlife biologists to improve strike-reporting. of grass provide abundant habitat for ground Mitigation is also critical on or adjacent to airports, squirrels and other rodent prey. Pigeons and where most strikes occur, including modifying other birds abound. Fences, light poles, and habitat to remove perches and making airports antennae make excellent hunting perches. less attractive to raptors. “Bird wailers” and falconry birds are employed to scare off raptors Collisions between birds and airplanes have and other wildlife. Raptors and owls are sometimes been of concern since Orville Wright reported relocated to safer locations. Some are shot. the first strike in 1905. Hawks have inspired and informed the development of human flight, but But questions arise about what mitigation methods the development of faster, quieter, and more are most effective. What will best discourage raptors powerful jet engines, and shrinking wildlife habitat from settling down at the airport? How far away put raptors at greater risk from aircraft strikes. must a raptor be relocated to ensure it doesn’t return? And how do banded birds help in this effort? 2009 was a turning point in attention to bird strikes, when US Air pilot Chesley “Sully” Sullenberger Dr. Richard Dolbeer, an ornithologist and landed an Airbus A320 on the Hudson River international leader in bird strike issues, has shortly after take-off, both engines crippled by proposed cross-referencing the BBL banded bird strikes. The event accelerated collaboration bird database with the National Wildlife by federal agencies, airport safety personnel, and Strike Database to expand data available to
PACIFIC RAPTOR 26 BAND RECOVERIES & ENCOUNTERS 2019 BAND RECOVERIES & ENCOUNTERS 2019
According to the Banded Bird Strike Database, three species of raptors top the list of banded birds struck by aircraft between 1990 and 2018: Peregrine Falcons (131),
Peregrine Falcons topped the Banded Bird Strike Database list of Red-tailed Hawks (83), and banded birds struck by aircraft between 1990 and 2018. Photo: American Kestrels (58). George Eade biologists and airport personnel. The goal of this Banded Bird Strike Database, notes Dolbeer, is to “provide a scientific foundation for policies and management actions to mitigate risk” and to create “safer skies for all who fly…birds and people!”
GGRO’s banding data and recoveries are part of this larger resource. GGRO’s Recovery #1129, Buzz Hull’s banded Red-tailed Hawk, is found in both the National Wildlife Strike Database and the BBL database and so A juvenile female Red-tailed Hawk (recovery #1575-B) sitting on a becomes part of this new cross-referenced database. So pole at the Point Mugu Naval Air Station in Ventura County. Red- is another Redtail banded by GGRO in September 2010, tailed Hawks came in second on the Banded Bird Strike Database's list of banded bird species struck by aircraft between 1990 and which struck a plane at San Jose International Airport 2018. Photo: Jeremiah Psiropoulos in June 2016 (Recovery #1407). While one banded hawk might not seem significant, the accumulated information provided by band encounters can help to refine questions and improve mitigation methods.
According to the Banded Bird Strike Database, three species of raptors top the list of banded birds struck by aircraft between 1990 and 2018: Peregrine Falcons (131), Red-tailed Hawks (83), and American Kestrels (58). Of the three species, Redtail strikes cause the greatest damage; and overall, buteos pose the fifth greatest strike threat to both military American Kestrels came in third, behind Peregrine Falcons and Red- tailed Hawks, on the Banded Bird Strike Database's list of banded and civilian aircraft (Dolbeer, et al. 2000; Zakrajsek bird species struck by aircraft between 1990 and 2018. Photo: & Bissonette 2005). Here are some of the trends George Eade revealed by the Banded Bird Strike Database:
27 FALL MIGRATION 2019 BAND RECOVERIES & ENCOUNTERS 2019 BAND RECOVERIES & ENCOUNTERS 2019
BANDED BIRD STRIKE DATABASE: On January 25, 2019, a juvenile female Red-tailed Hawk (recovery #1542) was trapped at the Joint • Red-tailed Hawk populations have increased Forces Training Base at Los Alamitos in Orange slightly between 1990 and 2018 and Redtail- County, CA. Banded by GGRO in October 2018, the aircraft strikes have increased substantially. Redtail was relocated from Los Alamitos about 100 The average age of Redtails struck by aircraft miles to Alpine County by biologist Derek Collins. is just under 3 years; adults are struck more Derek noted that there is currently a 15% return frequently than juveniles and are more likely rate for Redtails at the airbase. If a bird does not than juveniles to return to an airport when already have a band, he and other airport biologists relocated. Of 59 relocated banded Redtails, 52 band hawks with color bands (orange with white returned and were struck at the same airport; 7 letters) before relocation, making it easier to identify were struck at a different airport. those that return. They are also experimenting to see if increasing distance by increments of 50 • As post-DDT Peregrine Falcon populations miles decreases return rates of relocated hawks. increase, so do Peregrine-aircraft strikes.
While airport officials were unable to trap and The majority of Peregrine strikes between remove two of the hawks, and one died in 1990 and 2018 were juvenile birds in their first rehab of a probable airport strike, a final report summer or fall. provides more cheerful news. Biologist Jeremiah • American Kestrel populations declined between Psiropoulos photographed a juvenile female Red- 1990 and 2018, yet aircraft strikes increased tailed Hawk (recovery #1575-B) sitting on a pole substantially. Kestrels are also struck most often at the Point Mugu Naval Air Station in Ventura as juvenile birds. County on October 31, 2018. The Redtail had been banded by GGRO just eight days earlier, on October 23. Fortunately, she posed no menace This year, GGRO received 73 new band recovery to aircraft. Two and a half weeks later, the same and encounter reports from BBL: 47 Redtails, Redtail was photographed again, in San Ysidro, 16 Cooper’s Hawks, 4 Sharp-shinned Hawks, 3 just a few miles from the US-Mexico border. • Peregrine Falcons, and one each of Osprey, Northern Harrier, and American Kestrel. Five were reports of Redtails encountered at airports (Recoveries #1542, #1553, #1546, #1556, and #1575-B) and represent a range of outcomes for the hawks.
Dolbeer, RA SE Wright, & EC Cleary. 2000. Ranking the hazard level of wildlife species to aviation. Wildlife Society Bulletin 28 (2): 372-378.
Dolbeer, RA. 2018. Integration of Bird Banding Laboratory and National Wildlife Strike databases to enhance data quality and aviation safety. Presentation to Bird Strike Committee.
Zakrajsek, EJ, & JA Bissonette. 2005. Ranking the risk of wildlife species hazardous to military aircraft. Wildlife Society Bulletin 33 (1): 258-264.
PACIFIC RAPTOR 28 BAND RECOVERIES & ENCOUNTERS 2019
RECENT RECORDS
Marion Weeks
1389 Juvenile female Cooper’s Hawk 1491-C Juvenile male Red tailed banded on 9/26/15 by Ray Arpon and Hawk banded on 11/12/17 by Kaela found on 2/25/16 at Mill Valley, Marin Schnitzler; sighted and reported County, CA; thought to have hit something by Robert Hinz for the third time in as it had a detached retina, and was the same Mill Valley, Marin County, euthanized on admission. Reported by CA neighborhood on 10/28/18. Kate Lynch of WildCare of San Rafael. On 6/5/19 a former GGRO intern, Elizabeth Wommack, now Curator and Collections Manager of Vertebrates for the University of Wyoming, spent a couple days at the Museum of Vertebrate Zoology at University of California, Berkeley. While Beth prepared this banded Cooper’s
Hawk for their skin collection, she Encounter 1526. Photo: Victor Brouk discovered the bird had been shot. 1526-B Juvenile male Red-tailed 1418-B Juvenile Red-tailed Hawk Hawk banded on 8/14/18 by Teresa Ely; banded on 8/25/15 by Anna Fryjoff-Hung; sighted on 11/22/18 by Step Wilson at found on 2/15/19 injured at an intersection Hawk Hill, Marin Headlands, Golden Gate at San Jose, Santa Clara County, CA; National Recreation Area (GGNRA), transported by San Jose Animal Control to Marin County, CA. This Redtail was earlier Wildlife Center of Silicon Valley (WCSV). sighted at San Francisco’s Presidio, San Diagnosed and treated for a wing injury, Francisco County, CA on 8/16/18. the hawk was released 5/2/19. Reported Correction of this record is as by Jenny Liu and Ashley Kinney of WCSV. 1533 follows: An error was made in the This bird was earlier sighted at Milpitas, reading of the number on the color Santa Clara County, CA on 10/8/16. band originally reported to the Bird Banding Lab (BBL). This resulted in the species of the bird being inaccurate.
MARION WEEKS has been banding with GGRO since 1992 and has taken the initiative to dig deeper into band recoveries by reaching out to band reporters and rehabilitation facilities for encounter details and rehabilitation updates.
29 FALL MIGRATION 2019 BAND RECOVERIES & ENCOUNTERS 2019
Encounter 1533. Photo: Edward Kimball
Based on the misinformation, BBL identified it as a Cooper’s Hawk, but when Ed Kimball sent the photo to us, we could read the correct number and also identify the species as a juvenile Red-tailed hawk banded on 8/31/18 by Anne Ardillo. The bird was photographed Encounter 1538. Photo: Lam-Son Vinh on 10/19/18 about two miles south of Jenner, Sonoma County, CA. 1538-A Juvenile male Red-tailed Hawk banded on 11/5/18 by Ryan 1536 Juvenile female Red-tailed Byrnes; photographed at Huntington Hawk banded on 9/20/18 by Claire Central Park, Huntington Beach, Orange O’Neil; found freshly dead on road County, CA by Lam-son Vinh on 1/3/19. on 12/8/18 by Rebecca and William Bouch. They believe the bird had 1538-B Juvenile male Red-tailed been hit by a car just northeast of Hawk banded on 11/5/18 by Ryan Henry, San Luis Obispo County, CA. Byrnes; photographed on 12/29/19 while sitting on a light pole near the 1537 Juvenile female Peregrine maintenance area of the same park Falcon banded on 11/1/18 by Teresa at Huntington Beach, Orange County, Ely; found grounded 1/19/19 near the CA; reported by Roger Schoedl. Oakland International Airport, Oakland, Alameda County, CA and taken to 1539 Juvenile female Red-tailed Hawk Sulphur Creek Nature Center (SCNC). banded on 8/23/16 by Natalie Torres; was SCNC staff examined the bird and found brought to Peninsula Humane Society nothing amiss but noted she did not eat (PHS) on 7/16/18 after being found at during her captivity and was released an intersection at San Francisco, San 1/22/19; reported by Samantha Conner Francisco County, CA. Caught due to who exclaimed, “She was huge!” injuries that usually result from being hit
PACIFIC RAPTOR 30 BAND RECOVERIES & ENCOUNTERS 2019
by a car or flying into a window, it was on a seventh-floor balcony at San bleeding from the mouth but also had Francisco, San Francisco County, a puncture of wound of unknown origin CA and taken to PHS; due to its extending from the abdomen towards badly fractured wing, the bird was the base of the tale. Minimally responsive, euthanized; reported by Nicole Weger. the hawk was euthanized that same Juvenile female Red-tailed Hawk day; reported by Nicole Weger of PHS. 1542 banded on 10/1/18 by Lora Roame; 1540 Juvenile female Cooper’s Hawk trapped at the Joint Forces Training Base banded on 10/14/18 by Jean Perata; at Los Alamitos, Orange County, CA by “a pile of feathers with back and leg Derek Collins, Animal and Plant Health bones and the band on one leg” were Inspection Service (APHIS) biologist on found on 11/11/18 at Grey Lodge Wildlife 1/25/19. This bird was relocated about Area, Butte County, CA by Gary Zang. 100 miles away to Alpine County, CA.
1543 Juvenile male Red-tailed Hawk banded on 9/11/18 by Teresa Ely; hit by a car on 12/15/18 near Ortonville, Ventura County, CA; taken to Ojai Raptor Center where it was found to be severely emaciated (672 grams), infected with roundworms, and had coccidiosis: he was treated and released Encounter 1541-A. Photo: Peter Beeler on 1/23/19 weighing 1121 grams; 1541-A Juvenile male Red-tailed reported by Elizabeth Chouinard. Hawk banded on 9/20/18 by Marc Juvenile female Cooper’s Hawk Blumberg; photographed by Peter 1544 banded on 10/5/18 by Taryn Orlemann; Beeler on 11/14/18 as it was perched “the very decomposed body” of this atop a light pole by the San Francisco Cooper’s Hawk was found by a residential Bay, San Francisco County, CA. garage on 12/29/18 at Santa Ynez, Santa 1541-B Juvenile male Red-tailed Barbara County, CA; reported by 12- Hawk banded on 9/20/18 by Marc year old Kylie LaPointe and her father. Blumberg; photographed when Juvenile female Sharp-shinned perched on a tree branch by Robert 1545 Hawk banded on 10/3/18 by Brian Martin and two other GGRO banders Tsuru; sighted at Garden Grove, Orange on 1/13/19 at Buena Vista Park, San County, CA on 11/15/18; reported by Francisco, San Francisco County, CA. Marisela Rivera who stated, “it got 1541-C Juvenile male Red-tailed locked up in the cage where it entered Hawk banded on 9/20/18 by Marc to try and eat my [parakeets].” Blumberg; found injured on 4/25/19
31 FALL MIGRATION 2019 BAND RECOVERIES & ENCOUNTERS 2019
1546 Juvenile male Red-tailed Hawk 1551 Juvenile male Peregrine Falcon banded on 8/16/17 by Laura Echavez; banded on 10/25/07 by Terry Mead; killed by Matthew Stevens, APHIS found weakened on the side of Hydaburg biologist, at Travis Air Force Base, Highway, at Prince of Wales Island, Solano County, CA on 9/25/18 as the Alaska on 5/5/18 by Susan Culliney and bird presented a danger to aircraft. Melanie Smith while scouting sites for
1547 Juvenile male Red-tailed Hawk banded on 11/5/18 by Buzz Hull; found as roadkill on 1/21/19 four miles east southeast from Stevinson, Merced County, CA; reported by Hector Valtierra, adjunct professor at Cuyamaca College.
1548 Juvenile male Red-tailed Hawk banded on 8/29/18 by Vanessa Cabrera; remains found on 11/3/18 near off-ramp of Highway 85 at Saratoga, Santa Clara County, CA; reported by Earl Magnone.
1549 Juvenile male American Kestrel banded on 9/7/18 by Will Rose; found dead on 9/19/18 “freshly run over” on road northwest of Watsonville, Santa Cruz County, CA; reported by Encounter 1551. Photo: Susan Culliney Freddy Menge who had watched a the upcoming Southeast Alaska Birding kestrel hunting from a wire above the Trail. They carried him from Hydaburg overpass for several days prior. Highway to Craig, a ferry trip from Hollis to Ketchikan, and then a commercial flight 1550 Juvenile female Red-tailed to Sitka to the Sitka Raptor Center. It is Hawk banded on 11/3/18 by Catherine speculated that he was worn out from Fisher; found dead and headless the northward migration; he refused to on 11/14/18 in a pasture with native eat and died; no injuries or head trauma oaks at Sonoma, Sonoma County, were found. Of note, Susan Culliney, CA; reported by Barbara Roy. a GGRO intern in 2004, now works as Policy Director for Audubon Alaska.
1552 Juvenile male Red-tailed Hawk banded on 12/6/18 by Candace Davenport; found on 3/8/19 freshly dead of unknown cause in a field at Bird’s Landing, Solano Recovery 1550. Photo: Barbara Roy
PACIFIC RAPTOR 32 BAND RECOVERIES & ENCOUNTERS 2019
County, CA; reported by Eric Shelton. 1557 Juvenile male Cooper’s Hawk banded on 10/4/17 by Laura Booth; found 1553 Juvenile male Red-tailed Hawk on 12/13/18 freshly dead in backyard at banded on 9/3/18 by Kirsti Carr; caught Half Moon Bay, San Mateo County, CA; and killed on 3/28/19 during animal reported by Krista Alexander who believes control operations as it and two other it flew into something and broke its neck. Redtails spent a couple of days on a runway at Moffett Federal Airfield, 1558 Juvenile female Cooper’s Hawk Mountain View, Santa Clara County, CA; banded on 10/5/18 by Brian Smucker; reported by Eric Chow, APHIS biologist. banded leg found on 11/11/18 near a koi pond on large wooded “very bird-friendly 1554 Juvenile male Red-tailed Hawk property” at Los Osos, San Luis Obispo banded on 9/4/17 by Ed Sotello; found County, CA; reported by Gloria Zamora. grounded on 11/4/18, perhaps hit by a car at Belmont, San Mateo County, 1559 Juvenile female Cooper’s Hawk CA; taken to PHS where it was treated banded on 9/19/18 by Kathleen Grady; for injuries, but died the next day; found on 12/8/18 at Los Osos, San Luis reported by Greg Hassett of PHS. Obispo County, CA; reported by Kathy Duncan of Pacific Wildlife and unable to 1555 Juvenile female Red-tailed Hawk locate the record of this bird though she banded on 11/2/17 by Marion Weeks; recalled the dead bird was very skinny. found dead on 4/22/19 along Highway 5 near Kalama, Cowlitz County, WA; 1560 Juvenile male Red-tailed Hawk Department of Transportation workers banded on 12/3/17 by Emily Weil; leg with reported the bird to Glen Kalisz, the metal band on it and part of the rib Conservation Agency personnel for cage found on 5/10/19 on a trail at the Washington state who reported it to BBL. Kohl Mansion, Burlingame, San Mateo County, CA; reported by Jim Taschetta. 1556 Juvenile female Red-tailed Hawk banded on 9/1/18 by Lynn Schofield; 1561 Juvenile female Red-shouldered found on 11/26/18 at Travis Air Force Hawk banded on 8/29/16 by Teresa Ely; Base, Fairfield, Solano County, CA with died on 5/23/19 after it “slammed into wounds on dorsal side of both wings, [a second floor] window and broke its “elbows” scraped and cut up, and a neck” at San Jose, Santa Clara County, scrape wound near tail plus internal CA reported by Jesus Plancarte. injuries, but without any broken bones. Brought to Suisun Wildlife by military 1562 Juvenile male Red-tailed personnel where the bird died two Hawk banded on 9/10/18 by Kirsti days later; reported by Kris Reiger. Carr; found dead on 12/11/18 near a chicken coop at Bishop, Inyo County, CA; reported by Hari Nam Elliot.
33 FALL MIGRATION 2019 BAND RECOVERIES & ENCOUNTERS 2019
1567 Juvenile male Cooper’s Hawk banded on 10/19/18 by John Ungar; banded bone and another bone found on 6/23/19 by Rochelle Bening’s four- year-old son partially covered by leaves in their backyard at San Bruno, San Mateo County, CA. Rochelle noted that at the age of two, her son became interested in bones on Halloween and now wants to
Encounter 1563. Photo: Eric Figura be an archeologist. That very morning, he had asked his mom if they could 1563 Juvenile female Cooper’s Hawk “go on an adventure to find bones.” banded on 9/30/16 by Rosa Albanese; banded leg bone and three feathers 1568 Juvenile Red-tailed Hawk banded only found on 12/24/18 in a backyard on 9/27/2004 by Claire O’Neil; hit by just 10-15 feet from Umpqua River a car at Sebastopol, Sonoma County, behind a house at Glide, Douglas CA on 7/4/2019 and picked up by Brad County, OR; reported by Eric Figura. Marsh of the Santa Rosa Bird Rescue Center (BRC); he observed its mate 1564 Juvenile male Red-tailed Hawk flying above them and calling out then banded on 9/8/18 by Catherine Fisher; sitting in a tree directly above him. With sighted 12/2/18 at Buena Vista Park, no broken bones but unable to stand San Francisco, San Francisco County, or self-feed, and suffering from spinal CA; reported by Robert Martin, a GGRO shock trauma with central nervous bander, who added that it stayed around system issues, the bird was rehabilitated the area for much of the winter. and then released at the same place 1565 Juvenile male Red-tailed Hawk on 8/16/19. Note: This is one of GGRO's banded on 9/18/08 by Jerry Hadfield; 2004 telemetry birds named Quentin. found dead, wet, and in rigor at a lake on 1569 Juvenile female Red-tailed Hawk 6/12/19 at Calabasis, Los Angeles County, banded on 10/11/18 by Bill Prochnow; CA; brought to the California Wildlife observed on 12/23/18 as it flew into a Center; reported by Samantha Orzech. power line and was electrocuted and 1566 Juvenile female Cooper’s Hawk fell to the ground; a rescuer took the banded on 9/20/18 by Marc Blumberg; bird to Napa Wildlife Rescue (NWR) reported by Jeremy Tonkin who found where it was treated, but eventually the bird dried out inside an old camper euthanized on 1/2/19; reported by Linnaea with broken windows on 6/6/19 on his Furlong and Juliana Viera of NWR. property at Gilroy, Santa Clara County, CA. 1570 Juvenile female Cooper’s Hawk banded on 9/23/17 by Steve
PACIFIC RAPTOR 34 BAND RECOVERIES & ENCOUNTERS 2019
O’Neill; found 12/22/18 on ground with blood in its mouth at a Lucky’s parking lot at Santa Rosa, Sonoma County, CA; it was dead on arrival at BRC; reported by Taylour Stephens.
1571 Juvenile male Cooper’s Hawk banded on 10/14/18 by Anne Ardillo; caught due to injury on 2/17/19 at Planada, Merced County, CA; taken to Stanislaus Wildlife Care Center where it was euthanized shortly after arrival as the injuries were severe and believed due to being hit by a car; reported by Veronica Sandow.
1572 Juvenile female Cooper’s Hawk banded on 10/6/12 by Dick Horn; found injured in a backyard on 2/24/19 at Bakersfield, Kern County, CA by the resident who called Animal Control; Encounter 1575-A. Photo: Gerald Friesen they failed to show so she kept the 1575-A Juvenile female Red-tailed bird in a box and took it to California Hawk banded on 10/23/18 by Rachel Living Museum (CALM) on 2/26/19. Miller; reported by bird photographer Due to the severity of the wing injury Gerald Friesen who saw this bird on the bird was euthanized that same day; 11/17/18 while at a sod farm at San reported by Chris Palmer of CALM. Ysidro, San Diego County, CA along with several other birds that were heading 1573 Juvenile female Cooper’s Hawk south into Mexico. He noted the border banded on 10/31/18 by Jeff Wilcox; wall was about 200 yards away. found dead on 2/18/19 on a path to the river and under trees at Soquel, Santa 1575-B Juvenile female Red-tailed Cruz County, CA; reported by Melinda Hawk banded on 10/23/18 by Rachel McComb who noted there was a puncture Miller; photographed while sitting wound to the chest of unknown origin. on a pole on 10/31/18 by Jeremiah Psiropoulos, APHIS personnel at Point 1574 Juvenile female Cooper’s Hawk Magu Naval Airbase. He noted that this banded on 9/19/18 by Steve O’Neill; found bird was not a menace to aircraft. freshly dead on 10/2/18 on road traveled by Ranger Mark Sensenbach and others 1576 Juvenile male Red-tailed Hawk on the way to their office at Arroyo banded on 8/26/18 by Steve Rock; Grande, San Luis Obispo County, CA.
35 FALL MIGRATION 2019 BAND RECOVERIES & ENCOUNTERS 2019
caught due to injury on 2/3/19 at South 1580 Juvenile male Red-tailed Hawk San Francisco, San Mateo County, CA; banded on 8/23/18 by Claire O’Neil; found taken to PHS and euthanized due to on 12/11/18 at Ventura, Ventura County, injuries; reported by Sedef Tekin of PHS. CA close to the Ojai Raptor Center (ORC); bird was lethargic and had injury under 1577 Juvenile male Red-tailed Hawk the tongue; treated then released 1/18/19; banded on 9/8/18 by Michael Armer; reported by Elizabeth Chouinard of ORC. sighted on 1/29/19 near UCSF Hospital at San Francisco, San Francisco County, 1581 Juvenile female Red-tailed Hawk CA; reported by Rudy Warren. banded on 11/5/18 by Kirsti Carr; a homeless man brought the deceased bird to Newport Mesa Animal Hospital on 1/4/19 and reported that it was found in the middle of Newport Boulevard, Costa Mesa, Orange County, CA; reported by staff member Lily Cole.
1582 Juvenile male Red-tailed Hawk banded on 10/17/18 by Brian Tsuru; while driving patrol duty on 8/21/19, Shane Zook observed the Redtail swoop down in front of a pickup and get hit; he stopped and picked up the dead bird about 7.5 miles from the Deschutes River Woods, Deschutes County, OR.
Encounter 1578. Photo: Georgia Kinninger 1583 Juvenile male Cooper’s Hawk 1578 Juvenile male Red-tailed Hawk banded on 10/13/12 by Toby Rohmer; banded on 12/3/2017 by Emily Weil; few lower leg with band on it found on feathers and color banded leg bone found 4/5/19 and the other leg found the next on 8/16/19 in open space at a retreat day at Guerneville, Sonoma County, center at Burlingame, San Mateo County, CA; reported by Michael Hasley. CA; reported by Georgia Kinninger. 1584 Juvenile female Red-tailed Hawk 1579 Juvenile male Red-tailed Hawk banded on 8/19/17 by Dian Langlois; banded on 8/26/18 by Michele Garcia; found in a pool on 8/21/19 near the Cliff flew into a window of a home at Bodega House at San Francisco, San Francisco Bay, Sonoma County, CA on 12/21/18 County, CA; the bird was described and the resident transported it to as “alert, feisty, [and] stable though BRC for care but it died on 12/23/18; initially sort of listing to one side” reported by Taylour Stephens of BRC. when rescued; released the next day; reported by Kendra Jabin of PHS.
PACIFIC RAPTOR 3636 BAND RECOVERIES & ENCOUNTERS 2019
1585 Juvenile male Northern Harrier 1591 Juvenile female Red-tailed banded on 10/16/12 by Marion Weeks; Hawk banded on 8/31/18 by Olivia both legs, one banded, and few feathers Wang; photographed on top of along with “scraps of hide of some small telephone pole at Colusa National animal” were found on 5/26/19 at Santa Wildlife Refuge, Colusa County, CA Venetia area of San Rafael, Marin County, on 1/10/19; reported by Ellie Kidd. CA; reported by Laura Moore-McClelland. 1592 Juvenile male Red-tailed Hawk 1586 Juvenile female Sharp-shinned banded on 9/24/18 by Buzz Hull; Hawk banded on 9/14/18 by Olivia found dead in ditch along roadside Wang; found dead on a street corner at on 10/13/19 south of Valley Falls, Lake La Paz, Baja California Sur, Mexico on County, OR; reported by biologist 2/4/19 and noted by BBL as having been Steve Reidsma, who found the bird shot; reported by Andrew Stoltzfus. while doing a wetland survey.
1587 Juvenile female Red-tailed 1593 Juvenile female Cooper’s Hawk Hawk banded on 8/14/19 by Paula banded on 9/22/19 by Teresa Ely; a Eberle; found 8/22/19 dead on sidewalk few feathers and body with banded at South San Francisco, San Mateo tarsus found on 10/18/19 in remote County, CA and believed to have canyon by Luke Carlson while hunting been electrocuted by power lines in foothills north of New Cuyuma, above; reported by Falendra Ram. San Luis Obispo County, CA.
1588 Juvenile female Red-tailed 1636 Juvenile male Sharp-shinned Hawk banded on 9/24/16 by Steve Hawk banded on 9/22/18 by Erin Berry; Rock; died in route to the municipal caught after flying through an open shelter on 9/22/19 after striking a garage door toward windows at the back window at San Francisco, San Francisco of the garage on 1/29/19 at Pacifica, San County, CA; reported by Mara Lamboy Mateo County, CA; finders used a towel of San Francisco Animal Control. to gently secure the “very agitated” bird. The band number was read and then Juvenile male Peregrine Falcon 1590 the bird was released outside; reported banded on 10/12/18 by Serena Hubert; by Gary Gibbs and David Peterson. caught due to injury at Zamora, Yolo County, CA and brought to the California 1637 Juvenile female Sharp-shinned Raptor Center on 6/4/19; the falcon was Hawk banded on 9/17/16 by Steve euthanized the next day as its injuries Rock; found dead on 2/12/19 in front were not amenable to repair and the yard two days after a snowstorm at falcon was in poor condition; reported Chino Hills, San Bernardino County, by Bret Stedman who noted it also had CA; reported by Mark Wagner. an old healed fracture of its keel.
37 FALL MIGRATION 2019 BAND RECOVERIES & ENCOUNTERS 2019
1640 Juvenile male Red-tailed Hawk banded on 9/13/18 by Michaela Figari; photographed on 4/14/19 while perched in a tree at Scotts Valley, Santa Cruz County, CA; reported by Bethany Kilzer.
Encounter 1636. Photo: David Peterson Encounter 1640. Photo: Paul Kilzer 1638 Juvenile female Red-tailed Hawk banded on 12/1/17 by Traci Tsukida; found 1641 Juvenile female Red-tailed Hawk dead on 2/17/19 at Novato, Marin County, banded on 8/17/17 by Bill Prochnow; CA; reported by Hans Eide who described found at an intersection at San Francisco, the bird as “very thin and dried out.” San Francisco County, CA on 1/4/19 and reported as having hit something; Greg 1639 Juvenile male Red-tailed Hawk Hassett of PHS felt its injuries were of banded on 10/11/18 by Brian Tsuru; unknown origin and due to the fractured found dead on 3/10/19 at a home near femur, it was euthanized on intake. Forestville, Sonoma County, CA in • an enclosed area by chicken wire six feet tall; reported by Janet Beazlie.
PACIFIC RAPTOR 38 BAND RECOVERIES & ENCOUNTERS 2019
17 Kelsie McInnis; 2020 Kelsie
39 FALL MIGRATION 2019 BAND RECOVERIES & ENCOUNTERS 2019 BAND RECOVERIES & ENCOUNTERS 2019 Kelsie McInnis; 2020 Kelsie
PACIFIC RAPTOR 40 TURKEY VULTURE UPDATE
TH E STORY O F 3 6 8
Teresa Ely
urkey Vulture 368 moved as far north as is a household Novato and spent a lot T name for most of its time in the Marin GGRO volunteers. This Headlands. We were bird, along with four able to determine two others, was one of the roosting locations, one in first vultures tagged as Kirby Cove and another part of GGRO’s Vulture at Fort Baker. During the Research Project using a migration season, it was walk-in trap in December Turkey Vulture 368 seen from Hawk Hill. Photo: Olivia Wang seen on 41 different days 2017. The walk-in trap (sometimes multiple is a large modified dog run, with perches and sightings per day) from Hawk Hill and a handful of shade, and a rotting carcass positioned nicely to times from the banding blinds. During 2019, it was entice hungry birds. The vultures see the meat, the most frequently sighted tagged Turkey Vulture walk in a one-way door, and cannot walk back by a considerable margin, with 69 confirmed records out. During this first trapping attempt, two of from Hawk Hill and 7 from the banding blinds. the trapped vultures showed signs of poisoning If you see Turkey Vulture 368, you can report and were promptly taken to WildCare of San the sighting to the Bird Banding Laboratory Rafael, CA. One of the birds died from severe at reportband.gov. For those hawkwatcher’s visceral gout, but the other bird recovered and and bander’s that see 368 in the field, please was later tagged with a blue patagial tag, number continue recording this bird! Counting it daily 368. We were able to place a GSM transmitter might seem repetitious, but the frequency data on this bird and release it in January of 2018. of this vulture in the Marin Headlands is just as Turkey Vulture 368 is a “local” in the Marin important as any other movement ecology data. Headlands and regularly flies by Hawk Hill, but its The GGRO Vulture Research Project has been made transmitter also gave us a glimpse into its annual possible by generous donations made in memory movements. The transmitter collected data from of Paul Armer. Our great thanks to the Armer January 2018 until August 2018, then went silent just family for their long-time support of GGRO. before the migration season started. Vulture 368 •
41 FALL MIGRATION 2019 TURKEY VULTURE UPDATE
Satellite Transmitter Locations For Turkey Vulture 368 Kelsie McInnis; 2020 Kelsie
PACIFIC RAPTOR 42 OUTREACH
F I VE YEAR S O F MIGRATORY STORY
Audrey Yee
y 2020, over a thousand San Francisco lasting connections with raptors and our national and Marin County fourth and fifth graders parks and perhaps even to be inspired to work B have participated in five wondrous on behalf of these amazing avian predators. autumns of raptor education presented by During teacher and CFC staff-led classroom staff and interns of GGRO and the Crissy Field activities, students learn how to identify raptors, Center (CFC) of the Golden Gate National why they migrate, and how they adapt to changing conditions, which the young students relate to their own families’ journeys, whether moving houses, schools or countries. Their field trip to Hawk Hill brings the curriculum alive: they share sightings and identifications and witness a raptor release, all while enjoying and exploring their Bay Area national parklands. For many, this is their first time seeing or crossing the Golden Gate Bridge, and all of these impressions stay with them. It is our hope that these young people will continue to be amazed by and
Migratory Story students learn to spread their wings with 2019 curious about our natural world and become the GGRO Intern Emma Regnier. Photo: Paul Myers volunteers, scientists, and park rangers of tomorrow.
Parks Conservancy. San Francisco and Marin Honoring his wife Judge Jennie Rhine’s lifelong County public elementary school students who devotion to raptors and commitment to community participate in this innovative program will forever science as a GGRO bander, Tom Meyer underwrites be captivated by their classroom learning and Migratory Story in her name. With his unwavering experiences in the field, hopefully to make generous support, we continue to soar higher. •
AUDREY YEE is in her sixteenth year at the Golden Gate National Parks Conservancy where she singly manages the planned and commemorative gifts programs. Audrey has worked very closely with Tom Meyer, GGRO Director Allen Fish, and Crissy Field Center staff to bring the Migratory Story program to fruition.
43 FALL MIGRATION 2019 OUTREACH
PaHoua Lee, Community Services and Program Manager for the Crissy Field Center (CFC), helps students spot raptors at Hawk Hill. PaHoua manages all CFC aspects of the Migratory Story program and plays a critical role in the successful delivery of the program each year. Photo: Paul Myers
5-year Migratory Story 2015-2019 2015 2016 2017 2018 2019 Aggregate
Students Served 193 290 196 166 235 1080
Participating San Francisco 4 5 6 7 7* 13 Unified School District schools
Economically disadvantaged (free/ 86% 72% 92% 80% 75% 82.5% reduced-cost lunch)
Nonwhite N/A 92% 98% 92% 85% 91.75%
English language learners 72% 36% 42% 64% 54% 53.6%
Newcomers N/A N/A N/A 33% 26% 29.5%
Languages: English, Spanish, Cantonese; some years 3 4 4 4 3 5 included Mandarin and Tagalog
*Including one school from the Sausalito Marin City School District
PACIFIC RAPTOR 44 PINNACLES NATIONAL PARK
UNEXPECTED NEST-MATES
Gavin Emmons
lthough raptors Horned sitting high at the tend to follow nest site, then rising and A regular and flying to a nearby perch. well-studied behavior Two Red-shouldered patterns, they can also Hawks—an adult and a be unpredictable, making juvenile—proceeded to unexpected choices that scold and dive briefly at continue to reframe our understanding of their the adult owl. Scanning the nest site with my scope, actions and complexity. These unexpected moments I could see one nestling owl, mostly downy, about make raptors endlessly fascinating subjects that 2.5 weeks old by its size and feather development. challenge and broaden our assumptions. As a What came next was unexpected. I saw another raptor biologist at Pinnacles National Park for the nestling lift its head to scan the surrounding area. past 17 years, I have come to appreciate the many But it was a hawk nestling, not an owl! I blinked nuances of breeding raptor behavior at the park. and checked again, and sure enough, the second Perhaps the most exciting—and unexpected— nestling was a buteo, either a Red-shouldered or moments I have observed at Pinnacles National Red-tailed Hawk nestling, maybe a week old. Both Park were during the breeding season of 2018. nestlings settled down as the adult and juvenile On April 24, 2018, I hiked upslope through open Red-shouldered Hawks finished scolding the adult chaparral and oak woodland habitat to check the owl and left the area. The adult owl returned to the status of a breeding pair of Great Horned Owls. I nest, carefully settling to incubate and shade the set up a tripod and focused my scope on the nest young. Stunned, I quietly packed and left the area. site, a stick nest high in a Gray Pine, where I had What the heck was going on here? I had heard confirmed one of the adult owls incubating eggs on of raptors adopting nestlings from other species a previous visit. Sure enough, I saw an adult Great
GAVIN EMMONS is a raptor biologist for the National Park Service stationed at Pinnacles National Park in central California. Pinnacles is home to a rich diversity of wildlife including 13 breeding raptor species and one of the five core populations of California Condors.
45 FALL MIGRATION 2019 PINNACLES NATIONAL PARK
before. This is a rare event but has been noted among different diurnal raptor species—Bald Eagles raising an Osprey or Red-tailed Hawk nestling, even hawks raising a kestrel. But I have not heard of a case where an owl has adopted a hawk nestling. I was curious to see if the Great Horned Owls would continue to consider the hawk nestling one of their own, or if they would realize it was different, and an easy prey source.
I visited the owl nest site three more times in the next three weeks, and each time I saw the Great Horned Owl and buteo hawk nestlings, they were healthy, alert, and developing normally. The adult owls continued to feed prey to both nestlings and behaved toward the hawk young as if it were their own.
I posted photos of both nestlings at the nest site on social media and developed quite a following of raptor researchers and enthusiasts. No one else had observed this behavior between owls and hawks prior, and collectively we were all excited to see what Imagine lifting your binoculars for a routine nest survey, expecting to find a Great Horned Owl (GHOW) nestling or two, only to see would happen. It seemed likely that an adult owl this, a GHOW and buteo nestling side-by-side in a single nest. had taken a hawk nestling from a Red-shouldered Clockwise from previous page: GHOW nestling (~2.5 weeks old) and buteo hawk nestling (~12-15 days old) at Pinnacles National Park or Red-tailed Hawk nest, to be delivered to the owl on April 30, 2018. GHOW nestling (~4 weeks old) and buteo hawk nestling as prey. For whatever reason, the adult owls nestling (~16-19 days old) on May 4, 2018. Buteo hawk nestling (~22- 25 days old) stretching and showing feather development on May changed their minds. Perhaps one of the adults 10, 2018. Photos: Gavin Emmons delivered the uninjured hawk nestling, and then quickly flew off to find more food. Perhaps the owl Sadly, this unexpected nest effort ended with nestling was not hungry, and when an adult returned another unpredictable twist: the nest tree fell over to incubate, accepted both young as its own. prior to either nestling being old enough to fledge, and both likely perished in the tree fall. It was hard On May 10, 2018, I made my third visit. The owl not to be disappointed, but it was nevertheless a nestling was 5 weeks old and the hawk nestling fascinating view into a previously undocumented was approximately 22 to 25 days old. I was eager series of nesting behaviors that helped broaden to see the hawk develop further so that I could our understanding of raptor behaviors. What identify it to species. Would it survive to fledging? unexpected observations will we document next? Was it being fed by the adult owls at night? • Would it be able to adjust to diurnal hunting after developing with nocturnal foster parents?
PACIFIC RAPTOR 46 INTERN INTERVIEW
INTER-INTERN INTERVIEW: DR. LINNEA HALL ‘88
Taylor Barnes ‘19
ach season, we invite a current GGRO Intern founding, and now manages one of the largest to interview a previous GGRO Intern who has collections of bird nests and eggs in the world. E gone on to make important contributions to Thank you, both to Taylor, for conducting and conservation science. This year, 2019 Intern Taylor writing up this season’s Inter-Intern Interview, Barnes spoke with Dr. Linnea Hall, interned with and to Linnea for allowing us to print her story. GGRO in 1988, just four years after the program’s Where did your nature interest start? Were you an outdoorsy kid?
I was always active outdoors, but at age eight I started riding horses, and when I was eleven my family bought twenty acres in Moorpark, California that we transformed into horse stables. I trained and showed horses from the age of nine until my mid-thirties, and my last horse (for now) just passed away in 2014. I learned to absolutely love animals from my work with horses, and at ten years old declared that I would be some kind of animal biologist. At the age of twelve, I knew I would be a research veterinarian, and I interned with horse vets from then until my twenties and attended Cal Poly SLO (where I took lots of anatomy and physiology courses) from 1984 to 1988. In the last
2019 Intern Taylor Barnes holds a fledgling Barn Owl during pre- semester of my senior year I took Ornithology season banding training. Photo: Taylor Barnes from Dr. Eric Johnson, and everything changed!
TAYLOR BARNES became a 2019 GGRO Intern after graduating from the University of Nevada, Reno, with a BS in Wildlife Ecology and Conservation. Before joining GGRO, Taylor spent five years volunteering with her local wildlife rehabilitation facility where she developed a passion for conserving and protecting wildlife.
47 FALL MIGRATION 2019 INTERN INTERVIEW
Dr. Linnea Hall, Executive Director of the Western Foundation of Vertebrate Zoology (WFVZ), with WFVZ Collections Manager René Corado. WFVZ hosts one of the largest collections of bird nests and eggs in the world. Photo: David Moskowitz
In an instant I changed my mind about my career, In addition to tallying hawks in flight, I was able because I learned that I could be a researcher who to analyze GGRO hawk counts and compare them studied wild animals, and I fell in love with birds. with storm front information, and this became my first-ever scientific publication. After grad school, What attracted you to GGRO? I went on to teach ornithology as a professor at While at Cal Poly I did a little hawk rehabilitation CSU Sacramento, and later as the lead ornithologist stint, and with my new passion as a budding at the Western Foundation of Vertebrate Zoology ornithologist when I graduated, I looked for (WFVZ), and all the courses always include hawk an internship with birds of prey that I could IDs, of course. The internship also connected me slip into with little knowledge and a fair bit of with John Keane, who encouraged me to apply to gumption, and one that also had a good mentor. UC Berkeley for my master’s work, which set me Allen Fish was recommended to me, and once on my formal career path in the sciences. My time I met him, I knew I had found a good place to with GGRO was thus a wonderful foundational learn more about birds, nature, and science. experience, and I would strongly encourage any person interested in the natural sciences to apply. Did any part of the GGRO experience help set you on your career path? What was your master’s research?
Absolutely! Not only did I learn to ID hawks in Well, my actual project was on three species of mice flight for the rest of my life (thank you, thank in the White Mountains of California, conducting you!), I learned to collect and analyze field data. an experiment with them to see if I could induce
PACIFIC RAPTOR 48 INTERN INTERVIEW
them to have a population explosion during a There seem to be two schools of thought regarding drought by giving them supplemental food. But graduate school in wildlife ecology: (1) go the larger project we worked on in the White right into a PhD program after your Bachelor’s Mountains was much bigger than our individual degree; or (2) do a master’s first. What would you master’s projects. Over a three-year period (1989- recommend to a recently-graduated undergrad? 1991) I also checked hundreds of bird nest boxes I think that students benefit a lot by doing both every couple of weeks in pinyon-juniper and a master’s and a PhD, as long as they are at bristlecone pine woodlands; counted passerines on different schools and on different projects. With point count transects throughout the woodlands; two degrees you get broader experience as a and even helped John Keane with his project on scientist by conducting more projects. In addition, beautiful little Black-throated Gray Warblers. I you meet more colleagues and establish more learned to identify nearly a hundred bird species by connections, which is very helpful after graduate sight and sound, which set me on a life-long path school is over. And lastly, you get to learn from of counting all birds I come across and extolling more people, which is the most important part, the importance of learning their vocalizations! since graduate work is all about learning as much as you can so you come out with a good sense of How about your PhD? what you want to do for your career, how you want After finishing my master’s in 1992, I moved to to do it, and what you definitely want to avoid. southeastern Arizona to conduct point counts in eight “sky island” mountain ranges for a bird You have worked on an amazing range of monitoring project. It was a tremendous introduction research projects according to your publishing to the avifauna of that region, and I learned in record. Do you have a core research interest 1992 that there was very little information about that links many of these projects? many of the Neotropical breeding species of I have two “core research areas.” (1) I love issues the area, especially the Elegant Trogon. As a of habitat selection and habitat quality—why do result, in 1993 I raised funds to study the species, species use what they do, and what do they need for and convinced Dr. R William Mannan, at the optimum living, breeding, and behaving? (2) I also University of Arizona, to take me on as a student. love to work on population estimation projects and From 1993-1996, I looked for trogons all over nest monitoring projects—nowadays especially for southeastern Arizona, captured some and put on rare, endangered, or declining bird species—and use radio transmitters, determined what type of habitat that information to inform the US Fish and Wildlife they selected, and watched their breeding efforts Service, California Department of Fish and Wildlife, for thousands of hours at nest cavities. It was a and land management organizations about how privilege to work with this species; it truly is one their bird populations are doing and how best to of the most beautiful birds in North America. augment their populations. However, what lights me up more than anything is doing projects that make a difference for the animals I love. I have loved nature since I was a child, hate to see it destroyed, and
49 FALL MIGRATION 2019 INTERN INTERVIEW
of field time and classroom time over the past 17 years. My spring and summer are filled with avian conservation projects I conduct, and the fall and winter are filled with reporting and grant writing, Open Houses, and lots of kiddos visiting to learn about science and nature, which I LOVE. I am very fortunate to have the position I do.
How do you feel about the rise of Community Science in field ecology and conservation biology? Any concerns?
I think Community Science is fantastic and will be the way that science becomes accessible to everyone, rather than the lucky few. I oversee a community science project to monitor birds in the Santa Monica Mountains, and it is definitely 1988 GGRO Intern Linnea Hall prepares to release a juvenile Cooper's Hawk. Photo: Linnea Hall one of the best projects the WFVZ has going. Of course, training is always the key in any project, have always wanted to be a voice for the voiceless. I and it is definitely necessary in a Community think scientists owe a debt to the nature they study, Science project, but that is how we teach and to make sure that it flourishes. It is the cost of our include more people in the sciences, by opening degrees; we must help that which we come to know. what we do to the public and letting them share in the wonder of the natural world. You’ve been with the Western Foundation For more information on Dr. Hall and of Vertebrate Zoology (WFVZ) for a long the inspiring work of the WFVZ, please stretch. Tell us a bit about the museum. visit www.wfvz.org or peruse: What makes it compelling and interesting? What is a typical day at WFVZ for you? Purcell, R, LS Hall, and R Corado. 2008. Egg and Nest. Harvard Univ Press. There really is no typical day at a museum, I’ve found! The WFVZ, which is a non-profit public Kiff, LF. 2001. A history of the WFVZ 1956-1994. charity, holds the largest collections of birds’ Contributions to the history of North American eggs and nests in the United States. The museum Ornithology Vol. 2: 183. Nuttall Ornithology Club. has contributed to about 4,000 studies, on bird Our great thanks also to author/photographer/ subjects including breeding, toxicology, ecology, naturalist David Moskowitz for the photo of and conservation. I am the Executive Director, so Linnea and René. David’s forthcoming book, Bird I have to do some administration, of course, but I Nests of North America, will be out in spring of also am the lead scientist and for a long while was 2021. More info at www.davidmoskowitz.net and the lead educator, so I’ve had a beautiful mixture www.petersonbirdnests.com. •
PACIFIC RAPTOR 50 PEREGRINATIONS
W I N TE R RAPTOR S AT LYNCH CANYON
Jeremy Pallant
he morning of our trip, we were greeted by We all turned to watch the bird passing overhead, a thick fog that we soon discovered was showing the proportions of a large buteo. It was T blanketing much of the Bay Area. Despite tough to make out field marks against the backlit subpar weather conditions, we were still optimistic, sky, but then the bird stopped and began hover- and opted to make the trek to the East Bay. We hunting over a nearby field. As it stilled, the bird’s arrived at Lynch Canyon mid-morning, the fog legs bobbed like the needle on a sewing machine. A showing no signs of letting up. We paused upon Rough-legged Hawk! We decided to stick it out for our arrival to discuss our options: wait out the fog at least a few hours to see what the hiking trails had in hopes of clearer skies, drive home and wait for a to offer in terms of bird activity. day with more favorable weather, or throw caution Birding Lynch Road was tough. The fog was still to the wind and go ahead with our trip. As we thick and visibility was poor. At first, we saw little were deliberating, the silhouette of a large raptor more than California Towhees and Golden-crowned emerged from the fog at the edge of the parking lot. Sparrows. As we approached the split between the Tower Trail and the Valley Trail, sheets of rain began coming down. Matters were made worse when we were confronted by a large steer in the middle of the trail, staring us down and kicking at the mud in an effort to dissuade us from advancing. We didn’t need to be asked twice. We bundled up in our rain gear and hoofed back to the parking lot.
With our hopes waning, we had an early lunch at one of the barely protected picnic tables. Just as we were The interns search for hawks on a dreary morning under the about to throw in the towel, the weather conditions protection of a picnic table awning. Photo: Emma Regnier
JEREMY PALLANT joined GGRO as a 2019 Intern after graduating from Allegheny College with a BS in Environmental Science. Jeremy spent time trapping and banding songbirds at the Wing Island Birding Station in Cape Cod and Cusuco National Park in Honduras before moving out to the West Coast for the 2019 season.
51 FALL MIGRATION 2019 PEREGRINATIONS
began to change. The rain diminished to a drizzle Before we had a chance to get back on the trails, we and then ceased and the fog ceiling began to lift. In a spotted a large buteo, slowly approaching from the matter of minutes, it was a completely new day. north, its wings in a moderate dihedral. As it passed overhead, we got a terrific look at the ivory band at As conditions cleared, raptors took to the skies. the base of its tail and the clean white undersides of A pair of Rough-legged Hawks rose up in front its primaries and secondaries. Otherwise, the rest of of a nearby hill, surveying the grasslands. They the bird showed tones of dark chocolate brown and were soon joined by several Red-tailed Hawks of black. The dark-morph Rough-legged Hawk passed various ages, including some dark morphs. Farther overhead, passively eyeing the terrain below. We all off, two massive birds appeared above a ridge, trained our binoculars and scopes on the bird until it rising on a thermal and soaring together in broad disappeared to the south. circles. Upon further inspection with a scope, their Returning to the trail, we were taken aback by the sheer number of passerines that had emerged as a result of the much-improved weather conditions. The previously silent hills were now buzzing with birdsong and rustling branches as songbirds came out to forage. Black and Say’s Phoebes, Yellow- rumped Warblers, and Ruby-crowned Kinglets flitted between shrubs and the ground, searching for insects. A male Western Bluebird struggled to wolf down a centipede longer than its body. The metallic cries of California Scrub Jays and Red-shafted Flickers bounced off the canyon walls, and the cooing of Mourning Doves provided a peaceful backdrop.
As we re-approached the split in the trails, we were Juvenile Red-tailed Hawk seen at Lynch Canyon. Photo: John Davis relieved to find that the steer was gone. With the path now clear, we hiked to Lynch Reservoir. After identities became clear-two adult Golden Eagles! We a short slog through ankle-deep mud, we emerged watched as the eagles effortlessly ascended before at the reservoir’s edge. At the edge of the reservoir, disappearing into the cloud cover overhead. While a two White-tailed Kites roosted atop a bare tree. few of us continued to scan the hills, others turned Maggie pointed out several Northern Harriers their gazes lower, picking up a male American patrolling the far ridges, including a stunning adult. Kestrel, a White-tailed Kite in a snag, and a juvenile The valley echoed with flute-like whistles, which Northern Harrier skimming the grass. We were so Veronica identified as Western Meadowlarks. busy birding from the parking lot that we nearly forgot about the rest of the park. The path from to the reservoir wound up to the summit of a nearby ridge. Midway to the peak, we stopped to look at an adult Golden Eagle perched
PACIFIC RAPTOR 52 PEREGRINATIONS
Juvenile Rough-legged Hawk. Photo: John Davis
Adult Golden Eagle. Photo: John Davis
atop a radio tower, wings drooping, drying out after the rain. Across the valley, a juvenile Golden soared effortlessly over the crest of the opposite ridge, showing bright patches of white in its tail and wings.
While we’d been birding the reservoir, many Red- tailed Hawks had taken to the sky. On our walk back to the parking lot, there were times when we could The skies cleared at Lynch Canyon to reveal a juvenile Golden Eagle overhead. Photo: Susana de Trapaga see ten or more Redtails in a single field of view.
Among these Red-tailed Hawks were a handful happy for the day’s birds. After a dreary morning of of dark morphs. One of the juvenile dark morphs battling the elements, we had a terrific afternoon of flew directly over us. The bird had distinct “spikes” birding. A huge thank you to Step Wilson, Susana on the trailing edge of its wings, a trait unique to de Trapaga, and John Davis for helping us plan the Harlan’s Red-tailed Hawks. We didn’t see the bird trip to Lynch Canyon—a fitting culmination to a for long enough to confidently narrow it down to a wonderful 2019 intern season at GGRO. subspecies, but we all had a suspicion that it was a • juvenile Harlan’s Hawk.
By the time we reached the car, it was closing in on 4 pm and the sun was well on its way to setting. We were tired, damp, and covered in mud, but still
53 FALL MIGRATION 2019 The 2019 GGRO Intern Cohort brought great knowledge, skill, and passion to the 2019 season! Clockwise from top left: Jeremy Pallant, Paula Eberle, Taylor Barnes, Veronica Pedraza, Maggie Brown, Emma Regnier. Photo: GGRO A female American Kestrel photographed at Lynch Canyon Open Space Park in Solano County. Photo: John Davis
55 FALL MIGRATION 2019 VOLUNTEERS & DONORS 2019
he success of the Golden Gate Raptor Observatory rests on the shoulders of many people: the staff of the Golden Gate T National Parks Conservancy and the National Park Service; the donors who provide a critical budgetary boost for our research and operation; and an exceptional, creative and dedicated volunteer staff. GGRO volunteers give a minimum of 70 hours a year to the National Park Service, often closer to 100 hours. Double that is not unusual. But whether you give sweat, donations, or moral support, we deeply appreciate your sponsorship, your stepping up for raptor conservation. Great thanks to all of you, our volunteers, and donors, and colleagues.
GOLDEN GATE RAPTOR OBSERVATORY GRATEFULLY ACKNOWLEDGES:
2019 VOLUNTEERS Sarah Bohannon Laura Coatney Paige Fernandez Emily Abernathy Jeff Boissier Kay Conneely Michaela Figari Jeff Acuff Bob Boles Tom Conneely Allen Fish Jon Altemus * Robyn Boothby * Patrick Coughlin Erin Fisher Jan Ambrosini Ryan Bourbour Deborah Crooks * Dan Foldes * Anne Ardillo * Andy Bradshaw Susanna Czuchra Andrew Ford Jennifer Armer Nancy Brink * Candace Davenport Heidi Fuller Michael Armer * Jennifer Brown Belle Davis Lief Gallagher * Cynthia Armour Maggie Brown Dennis Davison * Jack Gedney Stefanie Arthur Marika Brown Susana de Trapaga Alison Gee Patricia Bacchetti Arden Bucklin-Sporer Carmen DeLeon * Brianna Gerard Lynn Bantley Marcia Budarf Russ DeLong Zeka Glucs Ryan Bantley Courtney Buechert Janine DeMartini Jan Gostlin Kathleen Barker Ryan Byrnes Crystal Dolis Maureen Grabowski Taylor Barnes Misty Cain Ben Dudek Kathleen Grady Eddie Bartley * Christina Cambie George Eade Alane Gray Don Bartling Ruth Cantwell Kathy Eagle Susan Greef Tim Behr * Christine Cariño * Wade Eakle Keith Gress * Ronald Berg Andrew Cayer Paula Eberle Chris Grogan Chris Bessett Linda Chambers Rich Eliason Joshua Haiman Sam Bessett Daniel Chelsky Catherine Elliott Mayu Hanabusa Lindsey Blessing Rich Cimino Nancy Elliot * Kris Handwerk Wiskes Marc Blumberg Conner Cimmiyotti Teresa Ely * Julie Hanft Robert Blumberg Jim Clausen Anastasia Ennis * Michael Harkins
The GGRO would not be able to function without the support of the program’s unpaid middle management team—our dedicated dayleaders. Thank you to all of the 2019 dayleaders for guiding their teams though another excellent migration season. Dayleaders are marked with an asterisk (*).
PACIFIC RAPTOR 56 VOLUNTEERS & DONORS 2019
Erica Harris Tani Myers Paulette Sherry Anne Ardillo JJ Harris Craig Nikitas * Shannon Skalos Marilyn Armbruster Melissa Hero Wendy Niles Tom Slyker Jennifer & Michael Armer Kimberly Hettler-Coleman Maureen Noon Ronald Smith Loretta Armstrong Cheri Hinkley Virginia Nowak Rachel Sneed Zinn Stefanie Arthur Nora Holmes Christine Okon Tim Stroshane Patricia Bacchetti Tom Holmes Brian O'Laughlin * Linda Sudduth Diane Bahr Laurasia Holzman Smith Ana Olivar Ally Sung-Jereczek Michelle Bain Calvin Hom Becky Olsen Candace Swimmer Lynn Bantley Sam Hontalas Claire O'Neil * Natalie Tan-Torres Juliana Barr & Allison Akanan Heather Hoyles Steve O'Neill Christina Tarr Reginald & Katherine Barrett Buzz Hull * Taryn Orlemann Craig Tewell Eddie Bartley & Josh Hull * Kenn Osborne Holly Thomas * Noreen Weeden Eric Jepsen Pat Overshiner Laura Thomas Mai-Liis & Donald Bartling Debbie Kahn Jeremy Pallant Gabriel Tigreros Anne Baxter Judy Kaufman Sarah Parnell Kate Traynor Ronald Berg Mamiko Kawaguchi * Sean Parnell Leslie Tribe Christopher Bessette John Keane * Julie Pearson Traci Tsukida Ardith Betts Brigid Keegan Veronica Pedraza John Ungar Elizabeth & Ted Bicknell Mary Kenney Jean Perata Michelle Unger Lindsey Blessing Jane Kim Jenni Peters Brad Valentine Robert & Marion Blumberg Melissa Kohner Jeff Peterson Emily Van Poetsch Marc Blumberg Doris Kretschmer Sean Peterson Douglas Vaughan Sara Bohannon Joan Lamphier Hailey Pexton Michael Voeltz Jeff Boissier Dian Langlois Roy Pisetsky Kristin Vorhies Robert Boles Natasha Lekach * Janice Podoll Olivia Wang Robyn Boothby Cheryl Lentini * Bob Power Noreen Weeden Gleneda Borton Patricia Lessard Bill Prochnow Marion Weeks Ryan Bourbour Allison Levin James Raives * Emily Weil Herb & Giselle Brandt Ann Linder Cricket Raspet Carol Weinstein Randy Breaux Cathy Loewen Sonja Raub Lisa Whitaker Donald Brennan William Ludan Emma Regnier Nelia White Lucille Breslow Tom Luster Eileen Richey Jeff Wilcox James & Patrice Britain Eric Lynch Beverly Riehm Ken Wilson Phyllis Browning Mary Malec Lora Roame Step Wilson * Lorraine Bruno Robert Martin Jeff Robinson * Bright Winn Stockton Buck Breanna Martinico Steve Rock Pat Wong Courtney Buechert Perry McCarty Paul Romanak Woody Woodbury Michael Butler Cindy McCauley Diane Rooney Jim Yampolsky Misty Cain Mark McCaustland Will Rose Pauline Yeckley Diane Caliva James McDermott Libby Rouan Sabrina Young Christina Cambie Kelsie McInnis Vanessa Roy Kara Zambricki Hugh & Pearl Campion Tomas McKay Jane Rudebusch * Gretchen Zantzinger Ruth Cantwell Paul Meadow Rod Santos Janet Carmona Horacio Mena * Peter Sapienza GENERAL SUPPORT John Caulfield Daniel Mestizo Juta Savage DONORS Linda Chambers Lisa Michl Sarah Sawtelle Heidi Munzinger Helen Chapman Jennifer Miller Jessica Schlarbaum Ritch Addison Daniel Chelsky Rachel Miller Linda Schneider George Almeida Shelley & John Chesley Margarita Montenegro Kaela Schnitzler Jan Ambrosini Rich Cimino Daniel Monteverde Jack Schofield Leslie Andrews Terry & Zoe Coddington Sue Morgan Lynn Schofield * Caryn & Joe Ansel Huguette Combs Nancy Mori Kylie Schubert Kay & Thomas Conneely
57 FALL MIGRATION 2019 VOLUNTEERS & DONORS 2019
Chris Kanit Cottrell Maureen Grabowski Hugh Harvey Kathy Jarrett Patrick Coughlin Brian & Nancy Graham Pamela Rose Hawken Craig Jones Paul Cox Alane Gray Lars Hellerslien Peter & Lindsay Joost Richard Crafton Chambers Deborah Crooks Reese & Kathleen Cutler Charles Cutting Susanna E Czuchra Ludek Dadok Jon & Cynthia D'Alessio Anne Darragh & David Ford Liz Davis Thomas Dawson & Jean Loo Tom Delebo Carmen Deleon Jason Dewees Kathleen Dillon Crystal Dolis Ben Dudek Barbara Duncan Steve Dykes Rick Elefant Richard Eliason Nancy Elliot Catherine Elliott Anastasia Ennis Marian Erdelyi Natalee Ernstrom Cynthia Feakins Leora Feeney Mark Fenn Richard Ferris Jeanne Fidler Scott Fife Virginia Fifield Michaela Figari Erin Fisher shows a juvenile Red-tailed Hawk with an unusual Harlan-influenced wing and tail pattern. Photo: Erin Fisher George & Patsy Fish Robert Fivis Wayne & Else Greenstone Melissa Hero Barbara Jording Ian & Sarah Flaherty David & Iris Gregoire Kim Hettler-Coleman Judy Kaufman Dan Foldes Dorothy Gregor Ms. Ann L. Heurlin John Keane Joseph Frank Keith Gress Diane Hichwa Susan Kelly Lillian Fujii & Steven Hayashi Earl Gress Cheri Hinkley & Laurie King Laura Fujii Christine Grogan James Broadstreet Timothy Kingston Heidi & Brian Fuller Jeffrey Gualco Jan Hintermeister Nancy Kittle Leo & Jane Gaspardone Mary Haack Lynn Hoerle & Jeff Wilson Melissa S Kohner Jack Gedney Mike Hall Calvin Hom Allison Kozak Alison Gee Julie Hanft Sam Hontalas Cheryl Kraywinkel Brianna Gerard Charlotte Harbeson Richard & Theresa Horrigan Pattie Krueger Angelo Gilbert Jill Harley Heather Hoyles Joan Lamphier Zeka Glucs Erica Harris W Hudson Barbara Lancaster Morey Goldstein JJ Harris Buzz Hull Jennifer Langum-McNeeley Janis Gostlin John Harris & Lisa Palermo John Irwin Art & Janine Lawrence Patricia Gotchall George Hartzell Victoria Jackson Mardi Leland
PACIFIC RAPTOR 58 VOLUNTEERS & DONORS 2019
Cheryl Lentini Dorothy McClain Gregg & Sharon Nicely Bob Power Patricia Lessard Maureen McCormick Catherine Nightingale David & Cay Pratt Peter Leveque Fran McDermott Wendy Niles David Presotto & Caryl Carr Allison Levin Peter McGuire Lois Nole Carol Prince & Jens Vindum Anne Libbin Tomas McKay Jill North Bill Prochnow & Ann Linder Terry Mead & Virginia Nowak Hulda Nelson H J Lindqvist Lois Reynolds-Mead Mr. and Mrs. Ed Nute John & Cynthia Rathkey David Loeb Paul Meadow Daniel O'Connell Gail Richardson Cathy Loewen Andrew Melomet & Kathy Odell Eileen Richey Carolyn & John Longstreth Diane Rooney Steven O'Donnell H Allan Ridley & Paul Lowrey & Diane Jones Horacio Mena Christine Okon Helen McKenna-Ridley Beverly Riehm & Randy Borcherding Lora Roame Duane & Barbara Robinson Steve Rock Janette Roletto Paul & Mara Romanak Elizabeth Rouan Matthew Rowlinson Maggie Rufo Dede Sabbag Walter Sakai Serena Salomon Ivan Samuels Shankar Sankararaman Peter Sapienza Juta Savage Charles & Susan Savage Michael Savino Charlotte Scherman Jessica Schlarbaum Marilyn Schmitz Linda Schneider Kaela Schnitzler John Schofield Hawkwatchers Ann Lindner and Wade Eakle. Photo by Nelia White Jinean Schofield Laurie Schofield Lowrey Kate Merriman Rebecca Olsen & Ken Wilson Leslie Schroeder Thomas Luster Ivan & Maris Meyerson Jessica O'Neill Anita Scuri Eric Lynch Carree Michel Gordon H Orians David Sexton Chris Macintosh Rachel Miller Ken Osborne Matt Shapiro David & Lynne Madison Steve Miller Patricia Overshiner Cynthia Shaw Ron Mallory Henry Mitchell, III Sean Parnell James Shea & Robert Martin Nancy Mori John Payne Katherine McKenney Nancy Martin Alida Morzenti Allan Peoples Jay Sheets Breanna Martinico Kathleen Mugele Amy Pertschuk Carrie Sherriff Sandra Massen Heidi Munzinger Jenni Peters James Shurter Kim Mauch Mikiye Nakanishi Jeffrey Peterson Martin Sidor Ronald Harold Maykel Soo-Hi & Alan Nayer Sean Peterson Shannon Skalos Perry McCarty, Jr Russell Nelson Roy Pisetsky Sandra Slichter Cindy & John McCauley Jody Newman Allan Plumb Mary Smith
59 FALL MIGRATION 2019 VOLUNTEERS & DONORS 2019
Brian Smucker Bright Winn Horacio Mena Eric Staton Sharon Solomon Katie Winslow Steve Miller Shannon Sweeney Hai-Thom Sota Kimberly A Witten Nancy Mori Nancy Thomas Edward Sotello Kathy & George Wolf Kathleen Mugele George & Sally Thomas Sheila Sousa Elizabeth Wommack Mikiye Nakanishi Paula Velez Patricia Spencer Pat Wong Brian O'Laughlin Jessamyn West Peggy Stanley Wayne Woodbury Patricia Overshiner Eric Staton Don Yasuda Jean Perata & IN MEMORY OF JENNIE Joan Stewart Nick & Kathleen Yatsko Dennis Davison RHINE Ann Stone Pauline Yeckley Jenni Peters Thomas Meyer Louisa Stone O'Brien Young Roy Pisetsky Polly Strahan Gary Zang Bob Power IN MEMORY OF GEORGE Deborah Stratmann Gretchen Zantzinger David Presotto & Caryl Carr SCHNAKENBERG Toby Suckow Bob Zeiss Jeff & Sarah Robinson Jennifer Schnakenberg Linda Sudduth Marin Horizon School Steve Rock Hal Sugishita Meriama Fund Maggie Rufo Mark Sutherland Petit Teton Foundation Peter Sapienza SILVER LUPINE CIRCLE Kirk Swenson Silicon Valley Community John Schofield LEGACY GIVERS Candace Swimmer Foundation David Sexton Allison Levin Christina Tarr UnitedHealth Group Tate & Curtis Snyder Thomas Meyer Constance Taylor Patricia Spencer Michael Murphy & Rachel Tennenbaum DATA ANALYSIS & Mark Sutherland Margaret Koehler Elise & Craig Tewell PUBLICATION FUND Kirk Swenson Jill North Holly Gail Thomas DONORS Linda Vallee Brian O’Laughlin Lynne A Trulio Mario Vitor Libby Rouan Jeffrey Acuff Hwei-Li Tsao Marion Weeks & Erika Walther Caryn & Joe Ansel John Ungar Stephen Blossom Stefanie Arthur Michelle Unger Jim Yampolsky Patricia Bacchetti THE GREGORY HIND John & Janet Upton March Conservation Fund William Barnaby ENDOWMENT FUND Brad Valentine Ardith Betts Leslie & Troy Daniels Linda Vallee Diane Caliva IN HONOR OF FRAZER Emily Van Poetsch Christina Cambie MEACHAM Richard Allen Vanderlugt Kay & Thomas Conneely Edith Summers Nick & Denise Villa Richard Crafton Chambers Mario Vitor Nancy Elliot IN HONOR OF JACK Karyn Vogel Catherine Elliott SCHOFIELD Margaret Ward Mark Fenn Noelle & Rob Schofield Thank you to Cellular Tracking Andrea Warner George & Patsy Fish Technologies for supporting Penelope Watson Heidi & Brian Fuller IN MEMORY OF KANANI GGRO's satellite tracking work. Marion Weeks & Alane Gray Stephen Blossom KAUKA Dorothy Gregor Emily Weil Glenn Backes Melissa Hero Carol Weinstein Christopher Barker Calvin Hom Paul Welles, Jr Jennifer Epstein J Pearce Hurley Elizabeth Wells Bonnie Faigeles & Sean Hoyer Mamiko Kawaguchi Virginia Welsh Annette Gaudino Joan Lamphier Nicholas Whelan Alison Hall Patricia Lessard Gretchen Whisenand Irena Li Ann Linder Cornelia White Lannae Long Thank you to Leica Camera Eric Lynch David Wiechers Maura Nolan Inc for providing optics for Cindy & John McCauley Edwin Williams & Usha Ranji GGRO's Hawkwatch program. Tomas McKay Joan Halverson Jen Sarche
PACIFIC RAPTOR 60 SUPPORT PARKS & PROGRAMS
SUPPORT THE GOLDEN GATE RAPTOR OBSERVATORY! Make a gift to the GGRO today and do your part to keep Bay Area raptors flying. Nineteen species of hawks, kites, osprey, falcons, eagles, and vultures travel over the Marin Headlands each year, and your support allows us to keep a pulse on their population changes, monitor their health, and track their movements throughout the Pacific region. Donate online at parksconservancy.org/DonateGGRO To donate by mail, send your check—written out to the Golden Gate Raptor Observatory—or credit card information with donation amount to GGRO at 201 Fort Mason, San Francisco, CA 94123. GGRO donors who give $35 or more annually receive a subscription to both Pacific Raptor and Season Summary. The Golden Gate Raptor Observatory is a program of the Golden Gate National Parks Conservancy in cooperation with the National Park Service and our work would not be possible without their support. You can further support the GGRO and other Parks Conservancy programs by becoming a Parks Conservancy member today.
BECOME A PARKS CONSERVANCY MEMBER Parks Conservancy members receive special benefits including a 15% discount (with proof of membership) on all product purchases made at our park stores and our webstore, invitations to the exclusive Member Hiking & Events Series, a subscription to Gateways, the Parks Conservancy’s quarterly newsletter, free admission to Park Academy classes; special courses of interest to nature lovers with topics ranging from gardening to climate change, and more. Visit parksconservancy. org/donate/membership-benefits for a full list of member benefits. Join online at parksconservancy.org/donate To join by mail, send your check—written out to the Golden Gate National Parks Conservancy—or credit card information with donation amount to Membership at 201 Fort Mason, San Francisco, CA 94123.
Back Cover: Adult female Rough-legged Hawk framed perfectly against Fort Cronkhite in the Marin Headlands. Captured from Hawk Hill. Photo by George Eade, a wildlife photographer with fifteen years’ experience as a GGRO Hawkwatcher. In addition, George also volunteers his time monitoring raptor nests throughout the north Bay Area. View more of George’s wildlife photography at https://geade.zenfolio.com/f351998031. A program of the Golden Gate National Parks Conservancy
Building 1064, Fort Cronkhite, Sausalito, CA 94965 (415) 426-5290 [email protected] • www.ggro.org
GGRO Director/Chief Editor: Allen Fish • GGRO Operations Manager/Managing Editor: Kelsie McInnis GGRO Hawkwatch/Outreach Manager: Step Wilson • GGRO Banding Manager: Teresa Ely 2019 Interns: Taylor Barnes, Maggie Brown, Paula Eberle, Jeremy Pallant, Veronica Pedraza, Emma Regnier Design Director: Carol Klammer • Designer Emeritus: Bill Prochnow • Research Director Emeritus: Buzz Hull GGRO Founder: Dr. Judd Howell • Parks Conservancy Director of Conservation Science: Janet Klein Parks Conservancy Sr Director of Stewardship & Community Science: Sue Gardner Parks Conservancy Exec VP, Projects, Stewardship, & Science: Sharon Farrell Parks Conservancy President & CEO: Christine Lehnertz
GGNRA–NPS Advisors Wildlife Ecologist: Dr. Bill Merkle • Chief of Natural Resource Management & Science: Dr. Alison Forrestel
Scientific Advisors Dr. Christopher Briggs (Colgate University) • Dr. Derek Girman (Sonoma State University) Dr. Michelle Hawkins (UC Davis) • Dr. Joshua Hull (UC Davis) • Dr. John Keane (US Forest Service) Dr. Ravinder Sehgal (San Francisco State University) • Dr. Elizabeth Wommack (University of Wyoming)
Pacific Raptor is the annual report of the Golden Gate Raptor Observatory, but we also welcome any raptorial articles based in the Pacific states and provinces.Pacific Raptor is published by the GGRO, a program of the Golden Gate National Parks Conservancy in cooperation with the National Park Service. The GGRO Season Summary is published in the winter. Make a donation of $35 or more at ggro.org for a subscription to both Pacific Raptor and Season Summary.
The Golden Gate National Parks Conservancy is the nonprofit membership organization created to preserve the Golden Gate National Parks, enhance the experiences of park visitors, and build a community dedicated to conserving the parks for the future. To become a member, phone (415) 4R-PARKS or visit parksconservancy.org.
The National Park Service was created in 1916 to preserve America’s natural, cultural, and scenic treasures, which today number 419, and to provide for their enjoyment by future generations. For information about the Golden Gate National Parks, phone (415) 561-4700, or visit nps.gov/goga.